drag and drop local zip file install for ExtensionManager
refactor install status logic to new Package.installPath() method. add flag to keep local zip files.
UI from @larz0. Refactor from table view to dialog.
revert changed to ExtensionManagerView
use LESS color variables
Dutch language updated (2)

Why it won't work the previous time?
Added missing SHA
Merge branch 'master' into adobe-jasonsanjose/extension-install-draganddrop

Conflicts:
	src/styles/brackets.less
Added logic to only process theme prefs events only when there is a theme selection.  Also changed ThemeManager around so that the style nodes for themes are reused. Update jsdoc
Redoing the dark theme to be more plain CSS and not rely on central variables.
Added logic to only process theme prefs events only when there is a theme selection.  Also changed ThemeManager around so that the style nodes for themes are reused. Update jsdoc
Merge branch 'themes-8457' of https://github.com/MiguelCastillo/brackets into themes-8457
Update strings.js
Fix inline editor colors.
Merge pull request #8459 from MiguelCastillo/themes-8457

[Themes] Logic to reuse theme style node
Use correct error message when renaming/deleting folder
Unified error message function, Title cased strings
Use ERR_TYPE_* constants
Consolidate all error dialogs into new method
Title Case FILENAME and DIRECTORY_NAME