deletet all gpu related files, changed alle .cu files to .cpp files and add...

deletet all gpu related files, changed alle .cu files to .cpp files and add the licence text where it was still missing

docs/cpu/Documentation/doc/install.html

-\section install_sec Installation
-
-\subsection step1 Step 1: CMake
-Download and install <a href="http://www.cmake.org/">CMake</a>. 
-If you have Windows OS oder X-Windows for Linux/Unix start <i>cmake-gui</i>.
-If you work in terminal start <i>ccmake</i>.
-\subsection step2 Step 2: project configuration
-You need set a path for <i>VirtualFluids</i> source code. It is allays <i>source</i> directory at the end of path.
-E.g. c:/vf/source. You need also set a path to build binaries. If you click <b>Configure</b> button start a project wizard and you can choose a compiler.
-Set <b>Grouped</b> and <b>Advanced</b> check boxes in CMake. In the group <i>USE</i> you have follow important options:
-\li USE_BOND    - using an agent based communication framework for fault tolerance BOND
-\li USE_METIS   - using a domain decomposition tool METIS    
-\li USE_MPI       - using MPI for distributed memory parallelization   
-\li USE_YAML     - using YAML
-\li USE_ZOLTAN - using domain decomposition tool ZOLTAN 
-There are externals library and you need additionally compile them.    
-\subsection step3 Step 4: project compilation
-Compile you project with suitable compiler.