Remove welcome project duplicate fix

Clean up welcomeProjectsFixed code - Issue #2823
Keyboard shortcut for open folder
Synchronized the menu sections with the current menus
Check for 'N' in save dialog even if focus is on a button
Added clarifying comment
Merge pull request #4134 from adobe/nj/issue-4109

Check for 'N' in save dialog even if focus is on a button
Merge branch 'master' of https://github.com/adobe/brackets into larz/framework-update-fixes
Merge pull request #3317 from albertxing/albertxing/2823

Remove welcome project duplicate fix
Merge pull request #4112 from TomMalbran/tom/issue-4023

Fix #4023: MenuSection object is out of sync with current Brackets Menus
Merge pull request #3972 from Chigurh/OpenFolder

[OPEN] Keyboard shortcut for open folder
Merge branch 'master' of https://github.com/adobe/brackets into larz/framework-update-fixes
Fixes based on NJ's feedback.