Added helper routines to rrPlugins.py and added new example

Added helper routines to rrPlugins.py and DataSeries, also added new
example that shows of rrPlugins.py changes in rrCreateNoisyDataShort.py
Bumped the version number of rrPlugins.py to 0.6.1
Added writeDataSeries and readDataSeries to rrPlugins.py
Updated comments in rrCreateNoisyDataShort.py
Created new folder, libplugins, to hold the roadrunner plugins api
Moved plugin api sources to libplugins folder
Created new folder, libplugins, to hold the roadrunner plugins api
Moved plugin api sources to libplugins folder
moved apps out of plugins
Moved examples
Moved C plugin example
Added README file to plugin lib examples
Changed so roadunner shared core is built by default
Various CMake changes to plugin related stuff
Re added deleted by mistake files
Updated paths: plugins -> libplugins
and library rrplugins_api is now just rrplugins
Minor cleanup after restructure
Minor update, project file
Changed roadrunners C target from rrc_api to roadrunner_c_api
Ran tests -OK
Add rows, cols and getColumnHeaders to DataSeries class
Added methods to get plugin metadata
Install roadrunner c api headers to rr/C
Fixed installation of missing headers