Merge pull request #5 from afuersch/master

Some type comments and fix if language level is null.
Bumped version to reflect the latest changes.
Introduced the new NuGet restore process.
DEV-313 Fix parsing issue of xing experience dates.
Merge pull request #6 from dasheddot/master

Fix parsing issue of xing experience dates.
Fixed compilation problems after the last PR, and extended bugfix to XING education as well.
Merge remote-tracking branch 'remotes/upstream/master'