Merge pull request #11 from feifanhe/master

Rewrite object tree
Multi fenu merging completed.
Patch for non-native button display style.
Enable auto scroll.
Fix multiple event triggering problem.
Fix how fenu open, now fenus open in respective document form.
Add fail safe when link doesn't exist.
Add xml format comment. Use this regulation for general help document generation.
Null button exception solved. Xml won't save unconfigured buttons.
Open same file will change focus instead of open new tab.
Save file (from main menu strip) now working.
Add triggered events from File menu items.