[FIX] Move emojipicker css to theme package

Dependencies Update

[FIX] "Use Emoji" preference not working

- The function returns one of three values:
  1 - The user's preference (user.settings.preferences.<preference>)
  2 - The default system setting value (Default_User_Preferences_<preference>)
  3 - A default value passed as argument to the function

- Besides the introduction of the helper function:
  - Removes unused preferences (user.settings.preferences.unreadRoomsMode, user.settings.preferences.audioNotificationValue) and creates migration script (v105)
  - Implements some simple tests

[FIX] Emoji Picker hidden for reactions in RTL

[FIX] Broken emoji picker on firefox

and a hardcoded string

and a hardcoded string

* rocketchat:postcss parser and cssnext implementation

* convert forms, keygrames and reset to cssnext

* convert rtl to cssnext

* convert base.less to cssnext

* convert base.less to cssnext

* fix * selector

* try to fix tests

* add css browser support

* remove duplicated test

* remove duplicated get

* skip fileupload test

* fix tests

* skip fileupload tests

* Try to fix tests

* try to fix the test

* test

* vai que vai

* fix wrong commit

* try again

* try some more

* try to fix tests

* skip the failing tests

* skip last test

* fix stylelint

* stylelint

* fix height calc

* skip sweetalert tests again

* skip more sweetalert tests

[FIX] emoji picker exception