add timestamp field to uORB msgs; sync timestamp whenever possible

msg/ekf_gps_position.msg

 # EKF blended position in WGS84 coordinates.
+uint64 timestamp		# time since system start (microseconds)
 int32 lat			# Latitude in 1E-7 degrees
 int32 lon			# Longitude in 1E-7 degrees
 int32 alt			# Altitude in 1E-3 meters above MSL, (millimetres)

msg/esc_report.msg

+uint64 timestamp		# time since system start (microseconds)
 uint8 esc_vendor					# Vendor of current ESC
 uint32 esc_errorcount					# Number of reported errors by ESC - if supported
 int32 esc_rpm						# Motor RPM, negative for reverse rotation [RPM] - if supported

msg/esc_status.msg

+uint64 timestamp		# time since system start (microseconds)
 uint8 CONNECTED_ESC_MAX = 8				# The number of ESCs supported. Current (Q2/2013) we support 8 ESCs
 
 uint8 ESC_VENDOR_GENERIC = 0				# generic ESC

msg/estimator_status.msg

+uint64 timestamp		# time since system start (microseconds)
 float32[24] states		# Internal filter states
 uint8 n_states		# Number of states effectively used
 

msg/follow_target.msg

+uint64 timestamp		# time since system start (microseconds)
 float64 lat			# target position (deg * 1e7)
 float64 lon			# target position (deg * 1e7) 
 float32 alt			# target position

msg/fw_pos_ctrl_status.msg

+uint64 timestamp		# time since system start (microseconds)
 float32 nav_roll
 float32 nav_pitch
 float32 nav_bearing

msg/geofence_result.msg

+uint64 timestamp			    # time since system start (microseconds)
 uint8 GF_ACTION_NONE = 0                    # no action on geofence violation
 uint8 GF_ACTION_WARN = 1                    # critical mavlink message
 uint8 GF_ACTION_LOITER = 2                  # switch to AUTO|LOITER

msg/gps_dump.msg

 # This message is used to dump the raw gps communication to the log.
 # Set the parameter GPS_DUMP_COMM to 1 to use this.
 
+uint64 timestamp		# time since system start (microseconds)
+
 uint8 len			# length of data, MSB bit set = message to the gps device,
 				# clear = message from the device
 uint8[79] data			# data to write to the log

msg/gps_inject_data.msg

+uint64 timestamp		# time since system start (microseconds)
 uint8 len			# length of data
 uint8 flags         		# LSB: 1=fragmented
 uint8[182] data		# data to write to GPS device (RTCM message)

msg/home_position.msg

 # GPS home position in WGS84 coordinates.
 
+uint64 timestamp		# time since system start (microseconds)
+
 float64 lat				# Latitude in degrees
 float64 lon				# Longitude in degrees
 float32 alt				# Altitude in meters (AMSL)

msg/input_rc.msg

+uint64 timestamp			# time since system start (microseconds)
+
 uint8 RC_INPUT_SOURCE_UNKNOWN = 0
 uint8 RC_INPUT_SOURCE_PX4FMU_PPM = 1
 uint8 RC_INPUT_SOURCE_PX4IO_PPM = 2

msg/iridiumsbd_status.msg

+uint64 timestamp				# time since system start (microseconds)
 uint64 last_heartbeat				# timestamp of the last successful sbd session
 uint16 tx_buf_write_index			# current size of the tx buffer
 uint16 rx_buf_read_index			# the rx buffer is parsed up to that index
@@ -11,4 +12,4 @@ bool ring_pending                   # indicates if a ring call is pending
 bool tx_buf_write_pending           # indicates if a tx buffer write is pending
 bool tx_session_pending             # indicates if a tx session is pending
 bool rx_read_pending                # indicates if a rx read is pending
-bool rx_session_pending             # indicates if a rx session is pending
\ No newline at end of file
+bool rx_session_pending             # indicates if a rx session is pending

msg/irlock_report.msg

 # IRLOCK_REPORT message data
 
+uint64 timestamp		# time since system start (microseconds)
+
 uint16 signature
 
 # When looking along the optical axis of the camera, x points right, y points down, and z points along the optical axis.

msg/landing_target_innovations.msg

+uint64 timestamp		# time since system start (microseconds)
 # Innovation of landing target position estimator
 float32 innov_x
 float32 innov_y

msg/landing_target_pose.msg

 # Relative position of precision land target in navigation (body fixed, north aligned, NED) and inertial (world fixed, north aligned, NED) frames
 
+uint64 timestamp		# time since system start (microseconds)
+
 bool is_static			# Flag indicating whether the landing target is static or moving with respect to the ground
 
 bool rel_pos_valid		# Flag showing whether relative position is valid

msg/led_control.msg

 # LED control: control a single or multiple LED's.
 # These are the externally visible LED's, not the board LED's
 
+uint64 timestamp		# time since system start (microseconds)
+
 # colors
 uint8 COLOR_OFF = 0 # this is only used in the drivers
 uint8 COLOR_RED = 1

msg/log_message.msg

 # A logging message, output with PX4_{WARN,ERR,INFO}
 
+uint64 timestamp		# time since system start (microseconds)
+
 uint8 severity # log level (same as in the linux kernel, starting with 0)
 uint8[127] text
-

msg/manual_control_setpoint.msg

+uint64 timestamp		# time since system start (microseconds)
 
 uint8 SWITCH_POS_NONE = 0		# switch is not mapped
 uint8 SWITCH_POS_ON = 1			# switch activated (value = 1)

msg/mavlink_log.msg

+uint64 timestamp		# time since system start (microseconds)
 
 uint8[50] text
 uint8 severity # log level (same as in the linux kernel, starting with 0)

msg/mission.msg

+uint64 timestamp		# time since system start (microseconds)
 uint8 dataman_id	# default 0, there are two offboard storage places in the dataman: 0 or 1
 
 uint16 count		# count of the missions stored in the dataman
-int32 current_seq	# default -1, start at the one changed latest
\ No newline at end of file
+int32 current_seq	# default -1, start at the one changed latest