DanbooruDownloader20151203
- Fix Issue #64: Add warning when file exists.
- Fix Issue #66: Empty folder created for Blacklisted tag when use custom filename.
- Implement Feature #67: Option to replace underscore in Tag to space
- Add Context Menu to open downloaded files.
- Set max width for data grid column to 300px.
- Add cookie login method for Gelbooru. Deprecate the UseAuth, replace with LoginType.