[BUILD,DOC] fixed some minor issues introduced with the GSL merge
[FEATURE] forward declaration of Matrix
[FEATURE] move conversion of ConsensusMap to own class

- put conversion of ConsensusMap into helper class
[FIX-#618] fix spelling errors in headers
Merge pull request #761 from hroest/feature/headerFixes

[FEATURE] moved ConsensusMap::convert into separate class to reduce coupling
Merge pull request #760 from hroest/feature/spellcheck

[FIX-#618] fix spelling errors in headers