Pull request for NDPluginROIStat

This adds new files:

Db/NDROIStat.template
Db/NDROIStatN.template
Db/NDROIStat8.template
Db/NDROIStat_settings.req

pluginSrc/NDPluginROIStat.h
pluginSrc/NDPluginROIStat.cpp
pluginSrc/NDPluginROIStat.dbd

and modifies the Makefiles to build the above.

Documentation is included in documentation/NDPluginROIStat.html

Tested multiple ROI on 1-D and 2-D mono data by comparing the results with a traditional ROI and Stats plugin.