moves nodelet_manager into camera namespace
adds option of utilising the worker threads parameter for the nodelet manager
adds topic remappings to sort the versious nodelets i/o (i.e. depth, rgb etc.)
removes (assumed) duplicated depth nodelets include thereby removing service registration error
adds arguments for switching on/off each processing module
Merge pull request #3 from bit-pirate/new_namespacing

Allow proper usage of namespaces for openni's nodes and nodelets