Fix file permissions

[strzibny]

I found some scss files to be executable, but I don't think they should be. And by updating to the newest version I found other new files that are executable as well:

$ gem compare jquery-datatables-rails 2.2.3 _ -kb
Fetching: jquery-datatables-rails-2.2.3.gem (100%)
Fetching: jquery-datatables-rails-3.2.0.gem (100%)
Compared versions: ["2.2.3", "3.2.0"]
  DIFFERENT files:
    2.2.3->3.2.0:
      * Added:
            lib/generators/jquery/datatables/
            app/assets/stylesheets/dataTables/bootstrap/2/jquery.dataTables.bootstrap.scss
              (!) Unexpected permissions: 100755
              (!) File is executable
            app/assets/stylesheets/dataTables/extras/dataTables.colVis.scss
              (!) Unexpected permissions: 100755
              (!) File is executable
            app/assets/stylesheets/dataTables/extras/dataTables.tableTools.scss
              (!) Unexpected permissions: 100755
              (!) File is executable
            app/assets/stylesheets/dataTables/src/demo_table_jui.css.scss
              (!) Unexpected permissions: 100755
              (!) File is executable
  DIFFERENT runtime dependencies:
    2.2.3->3.2.0:
      * Added:
            railties [">= 3.1"] (runtime)
            actionpack [">= 3.1"] (runtime)
  DIFFERENT development dependencies:
    2.2.3->3.2.0:
      * Added:
            rake [">= 0"] (development)