Merge branch 'hotfix/5.5.1'
Merge branch 'release/5.6'
Merge branch 'develop'
Merge pull request #4 from sitefusion/develop

Fixed customtree for xulrunner 24.0 and up
Merge pull request #6 from sitefusion/develop

Added 'clickItem', 'dblclickItem' and 'contextmenuItem' events to XULCustomTree
Removed lib/DatabaseObject. Updated .gitignore files.