assets: clean langs.css properly to let rails reboot correctly

Author: Trim

app/assets/stylesheets/contrib/RonRonnement-Classic.scss

@@ -4,7 +4,6 @@
 
 @import "../common/ac";
 @import "../common/generics";
-@import "../common/langs";
 @import "../common/markitup";
 @import "../common/statistics";
 @import "../common/doorkeeper";

app/assets/stylesheets/contrib/RonRonnement-Sepia.scss

@@ -25,7 +25,6 @@ $C_BD5: transparentize($C_BANDEAU, 0.17);
 
 @import "common/ac";
 @import "common/generics";
-@import "common/langs";
 @import "common/markitup";
 @import "common/statistics";
 @import "pygments/colorful";

app/assets/stylesheets/contrib/nightgrey.scss

@@ -2112,4 +2112,3 @@ fieldset.link {
 }
 
 @import "../common/statistics";
-@import "../common/langs";

app/assets/stylesheets/contrib/solarized/langs.scss

@@ -31,8 +31,6 @@ Licence CC-BY http://creativecommons.org/licenses/by/3.0/fr/
 @import url(http://fonts.googleapis.com/css?family=Numans);
 @import url(http://fonts.googleapis.com/css?family=Josefin+Slab:700);
 
-@import "langs";
-
 @mixin triangle_topleft($color) {
   width: 0;
   height: 0;