Remove welcome project duplicate fix

Clean up welcomeProjectsFixed code - Issue #2823
Keyboard shortcut for open folder
more robust filename checking
updated comment
remove unused local vars and redundant var
Merge branch 'master' into jeff/validate-win-filenames
rtc: move and reorder, added unit test
make apostrophe lass fancy (#3976)
Fix the buttons order in the Install with URL dialog
fix italian
undo/resubmit italian
update usage of new Dialogs API: done() does not chain, command handlers should return a promise.
update not yet translated version of Italian page to current English page
Backend changes to check extension update needs.

Exposing ALREADY_INSTALLED state to the UI.

completely handles the case of an already installed extension the installation of which
is canceled at confirmation time.

Install extension dialog handles NEEDS_UPDATE case and also passes
along the installed extension information to the caller.

Extension Manager now displays update mark and allows undo.

Checkpointing frontend work for installing update

Supports installation of updates.
Add ability to create multiple global key handlers that override KeyBindingManager. Refactor dialogs and code hints to use this.
Synchronized the menu sections with the current menus
Add a margin left to all the none left buttons
Always listen for sidebar resize.
Consolidate color matching regex into a single file and share across extensions"
Update copyright year. Remove unused vars from global list