Added props struct to devices, moving device properties such as identifier, ordinal, name, port from admin to device. Also make cleaner division between clock functions and admins, devices, etc.
Merge branch 'master' into device-props

Conflicts:
	src/admin.c
	src/connection.c
	src/device.c
	src/types_internal.h
Merge branch 'master' into device-props

Conflicts:
	include/mapper/mapper_db.h
	src/admin.c
	src/params.c
Merge branch 'master' into device-props

Conflicts:
	src/admin.c
	src/db.c
	src/device.c
	src/mapper_internal.h
	src/signal.c
	src/time.c
	src/types_internal.h
Added documentation of results from test/testspeed.c
Fixed some documentation comments.
Handle case where provided count value is negative.
Merge branch 'master' into device-props

Conflicts:
	include/mapper/mapper.h
	include/mapper/mapper_db.h
	src/admin.c
	src/db.c
	src/device.c
	src/signal.c
	src/types_internal.h
	test/testexpression.c
	test/testqueue.c
Cleaned up expression syntax documentation.
Fix serious bug in monitor batch requests of signal metadata.
Make automatic connecting a runtime argument.
Print link metadata in testmonitor.
Add missing include for stdlib
Print all connection metadata, reorganized.
Fixed reference counting bug in Python bindings when adding and removing signal callbacks.
Add missing connection properties to db.
Refactored mdev_timetag_now() -> mdev_now() and added equivalent monitor function mapper_monitor_now(). Also added Python bindings for these functions.
Removed use of data type lo_address in public API, since it is usually more straightforward to access host name and port directly.
Added test program that creates a device and adds 200 signals - useful for testing monitor batch-requests.
Added support for multiple values per key in mapper_message_t