Merge branch 'less'

* less:
  check less compilation for errors
  removed possibility to have rtl.less files in plugins
  switched to LESS variables in rest of template's css files
  unlessified and lessified a few more css
  fixed broken structure
  removed debug statement. sorry
  convert ini replacements to less vars first
  make sure calculations are correct
  lessified more files
  lessyfied another one
  lessyfied the first of template's CSS files
  fixed ini replacement to less variables stuff
  added missing lessc library
  add LESS support

Conflicts:
	inc/load.php
	lib/tpl/dokuwiki/css/basic.less