Add license information for the icons used
Show triggers and views

Also show the triggers and views in the DB structure tab.
Rename files to match class names
Allow all file names when opening a DB by drag & drop
Move preferences menu action to view menu
Fix window caption of edit field dialog called by popup menu

Fix the caption of the edit field dialog to show the correct table name
when it is called by the modify field action in the popup menu or the
toolbar.
Also remove one more useless debug message.