MINOR: Add a few tests for the database and the database cache (still tests missing)
MAJOR: Add sync down case 7 (fixes: create unknown file history marked as DELETED), fix database cache (do not remove deleted versions, simply don't add them); MINOR: Fix a few calls to File.exists (returns false for symlinks with nonexisting targets), replace FileUtil.getRelativePath with Path.relativize() methods, move createChecksum to TestFileUtil, add some Database Cache tests
Merge branch 'master' of github.com:binwiederhier/syncany