OpenMS/OpenMS — pull request #894 by aiche (2014-07-17 13:56:49+00:00)
Title: [FEATURE] improved 3rd party lib finding

This pull request bundles a couple of changes to the process of finding 3rd party libs

* switch from `CMAKE_FIND_ROOT_PATH` to `CMAKE_PREFIX_PATH`
* use of real find module for xerces-c and coin-or
* cleanup of existing find modules

The switch from `CMAKE_FIND_ROOT_PATH` to `CMAKE_PREFIX_PATH` was necessary since

* newer versions (`>= 2.8.12`) of the boost find module shipped with cmake had problems with `CMAKE_FIND_ROOT_PATH` on windows
* we were actually misusing `CMAKE_FIND_ROOT_PATH`. See for instance [this](http://public.kitware.com/pipermail/cmake-developers/2012-January/002850.html) post on the cmake mailing list where the relation between the different `CMAKE_*_PATH`s is explained