* added title for snippets
* title displays name of parent scope.
* when new TokenLocationFiles are created in the storage they are now returned as shared_ptr to ensure correct linking in the contained data.
* Storage::getTokenLocationsForLinesInFile() now always returns pairs of start and end locations.
* Adjusted code snippet view to regard the change described above.
* added SnippetMerger class that conducts the merging and snapping of TokenLocations to create snippets.
* added parameters for snippet snapping and merging to ApplicationSettings.
* added forEachStartTokenLocation() and forEachEndTokenLocation() to TokenLocationLine and TokenLocationFile.
* added < and > operators to TokenLocation that compare the location part (not the id).
Having only one access point to the Storage will simplify caching and parallelisation in the future. Also the two
accesses were never really independent of each other anyways, because in some cases they had to access both data sets.