Added IPositionControl2 and relative Implement files.

New IPositionControl2 interface implemented. This interface let the user specify a list of joints
to which apply the commands. Joints can be not sequencial and not ordered.

ImplementPositionControl2.h and IPositionControlImpl.cpp has also been created to correctly
call IPositionControl2Raw methods.

libYARP_dev/include/yarp/dev/ControlBoardInterfacesImpl.h
libYARP_dev/include/yarp/dev/ControlBoardInterfaces.h

were also updated to include the new interfaces.
IpositionControl2 linking fix, corrected temp_int

added "using IPositionControl::setPositionMode, ...";
and   "using IPositionControlRaw::setPositionModeRaw, ..."

in order to let ImplementPositionControl2 have access to all inherited methods.
fixed temp_int now correctly instatiate a vector of integer.
Added IVelocityControl2 and relative Impl, added const to the parameters passed to IPositionControl2 methods.
Added IControlLimits2 interface

IControlLimits2 add set/get Velocity limits methods and extend the
interface to be used for single joint, group of joints and all joints.
Corrected typo in comment.
Complited IControlLimitInterface2

This interface add a set/get velocity limit command and its vocab.
fix for IPositionControl2, removed double stops
Added vocabs for IPosition2, IVelocity2, IControlLimits2. Removed group methods where was not needed
Fixed revision issue. Added missing  StubImplVelocityControl2
Merge pull request #46 from barbalberto/coman

New Interfaces with group commands