[API,FEATURE,FORMAT] added IBSpectraFile class to FORMAT

 * IBSpectraFile can directly convert cXML to ibspectra format supported by isobar
 * includes test and documentation
 * as it is a pure csv based format it was not added separately to FileTypes
[FEATURE] FileConverter now supports the conversion from cXML to ibspectra

 * added conversion code to FileConverter
 * added corresponding topp tests
 * fixed minor issue in topp tests of MRMTransitionGroupPicker
 * unified add_test/ADD_TEST usage in src/test/topp/CMakeLists.txt
[INTERNAL] refactored code for modify string generation
[INTERNAL] use boost::shared_ptr instead of raw pointer
[NOP] updated feature/ib-spectra-format-export branch with changes from develop

 * should allow direct merge on github
 * Merge branch 'develop' into feature/ib-spectra-format-export

Conflicts:
	src/tests/topp/CMakeLists.txt
Merge pull request #666 from aiche/feature/ib-spectra-format-export

[FEATURE] ib spectra format export