Merge pull request #40 from hawesie/hydro-devel

Changes to how meta info is stored.
updated pkg name ros_mongodb_datacentre to ros_datacentre
Fixed multiple definition error in C++
Merge pull request #41 from hawesie/hydro-devel

Fixed problem with unicode strings in headers.
Added a ros_datacentre_cpp_client library to avoid multiple definitions of some symbols
Renamed the library to message_store and moved some files around
Merge pull request #42 from RaresAmbrus/hydro-devel

Fixed multiple definitions in C++
Working binary with pointclouds.
Made wait more obvious
Added inserter id and time to meta.
Added updated time and caller too.
Added update_id method for updating stored object using ObjectID.
Added examples of id-based operations.
Added example of way to log related events to message store.
Added point cloud test, but not including in compilation.
Changed order of MessageStoreProxy constructor arguments.

This was done to allow more natural changing of parameters in a sensible order. It's more likely you want to change collection name first, so that is the first parameter, leaving remainder as default.
Added cpp example of logging multiple messages together.
Added updateID to cpp client.
Cleaned up differences between two commits.
Merge branch 'hydro-devel' of https://github.com/hawesie/ros_datacentre into hydro-devel

Conflicts:
	ros_datacentre_cpp_client/CMakeLists.txt
	ros_datacentre_cpp_client/include/ros_datacentre/message_store.h