Revert "fixed project files for VS 2010"

This reverts commit a71913a3a38e956f3ca478ea862b73da6130bc1b.
revert "Revert "fixed project files for VS 2010""

This reverts commit beacf90c2f920d92b8cfc162778a13111fd04ed2.
added .sdf files to gitignore
Merge branch 'devel' of https://github.com/triAGENS/ArangoDB into devel