fixes #358

Problem: Unable to edit files ending with `.html` extension in File Manager

Workaround: For files ending with URL suffix - add `has_url_suffix=1` to $_GET and detect it while editing those files.
fixes #358

Problem: Unable to edit files ending with `.html` extension in File Manager

Workaround: For files ending with URL suffix - add `has_url_suffix=1` to $_GET and detect it while editing those files.
Merge pull request #557 from marekmurawski/issue-358

Fixes #358 - unable to edit '*.html' files in File Manager
Add empty robots.txt fixes #351
Eat cookies that were set from JS upon logout. Fixes #352
Fix some undefined property errors due to changes in Record
Fix bug where we check for username when none exists.
Fix undefined property bug when adding user due to Record change