Change in wiki formatting on - DruTeX/Latex

I have changed the default input format on to no longer process
DruTex commands, since these interprete the '$' sign as a start of latex
equation, which screws up cmake and bash code.

There is a new content type 'Mediawiki with DruTeX' which is the default +
DruTeX markup. I have converted the KDL pages to this new type and it seems to
work. Please review any pages you know of that use Latex. You need to be an
orocos-user or orocos-developer in order to update that content type. Normal
users can not use that content type, since it only adds confusion when
creating wiki content.

Another side effect is that 'regular' pages often contain a back-slash before
the $ sign, in order to disable DruTex. I removed some on various pages, if
you encounter a '\$' on an existing page, please edit that page and replace it
by a plain dollar sign.