Issue #1986418 by tompagabor, LewisNyman, idflood, jamesquinton, lauriii, emma.maria, danmuzyka, rteijeiro, scronide, frankbaele, Coornail, ekl1773, oresh, philipz | Bojhan: Update textfield & textarea style.

Issue #2207767 by temaruk, Coornail, rteijeiro, alexrayu, LewisNyman: Replace watchdog icons with Libricons.

- Patch #1116416 by Kars-T, Coornail: use 'Header set' instead of 'Header append' in .htaccess to avoid double encoding.