added nightly features support and update date format same as latest SubWCRev.exe

1.added keywords here. http://tortoisesvn.net/docs/nightly/TortoiseSVN_en/tsvn-subwcrev-keywords.html
2. Modify time format from %Y-%m-%d %H:%M:%S to %Y/%m/%d %H:%M:%S which is same as latest version