Refactored and fixed:

- Refactored, linted, fixed potential problems, enabled 'use strict'

Fixed:
- Added "Enable plugin synchronization" option
(Plugins and settings had been run always)

Implemented:
- Sync preset implemented.
- "Check integrity on saving" implemented.
- "Sanity check" implemented
It's mainly for debugging.

.eslintignore

@@ -0,0 +1,3 @@
+npm node_modules
+build
+.eslintrc.js.bak