Always build the YARP_manager library as STATIC

This is a temporary fix, the library should use a YARP_manager_API
macro for __declspec(dllimport/dllexport) on windows
[OS/SystemInfo] added environment info to platform information (TODO: actually retrieve that info)
added --which flag to yarprun to retrieve remote location of script files from yarpmanager's scriptBroker
[OS/SystemInfo] retrieve environment variables on host machine
Using generic Things object to access portable data. (Towards having more stable scripting API in portmonitor)
implementing some methods for carrier sender modifier
first implementaion of carrier sender modifier
portmonitor: Cleaning up yarp::os::Things class from yarp::sig namespace by moving the implementaion of Things class into swig things.i. modifyOutgoingData() gets a PortWrtier object instead of Portable now! PortCoreOutputUnit will refuse writing data to an output port if acceptOutgoingData() returns false
implementing time event
now that time can be tweaked, added a basic 'yarp time' test to show it
Using generic Things object to access portable data. (Towards having more stable scripting API in portmonitor)
fixing issue #119 for the portmonitor carrier
fixing a bug related to the issue #119
don't try to interpret hex strings that are too long to represent

fixes #166, thanks @ale-git
[ros] change XmlRpc namespace to avoid conflict

YARP and ROS both use the XmlRpc++ library.  When YARP is
compiled statically, these libraries can conflict if the
user is also linking ROS.  (This is not a problem when
YARP is compiled as a shared library, where the
XmlRpc-related symbols are not exposed).  To support
static linking, the XmlRpc namespace in YARP is renamed
to YarpXmlRpc.  See #167
Merge pull request #168 from robotology/portmonitor

update portmonitor
Add yarp/os/Things.h to YARP_OS_HDRS in CMakeLists.txt
Merge pull request #170 from traversaro/patch-1

Add yarp/os/Things.h to YARP_OS_HDRS in CMakeLists.txt
portmonitor: removing unecessry files
portmonitor: fixing simle_modifiucation example