Fixing an issue with the cxx-generator when it is invoked within a folder structure containing 
hidden versioning information (.svn, .git folders etc.). Ignore '.svn' and '.git' etc.
folders and do not interpret them as Javascript engine targets like the 'spidermonkey' folder.
Merge pull request #27 from DarraghCoy/master

Fix an issue with the handling of .svn, .git etc. folders in the cxx-generator