Fix #42 -- Bad dialog for import library from menu. Also added import source folder from Arduino menu

Fix #42 -- Bad dialog for import library from menu. There were inonsistencies between the pages being generated for display. Changed to use a sourceGroup and create teh pages "last minute" via addPages().


Added import a source folder as an option in the Arduino menu.

There were also a few minor  tweaks on spelling etc and some changes on the indents.