Separate FairRoot installation from the experiment code

Introduce new environment variable FAIRROOTPATH and cmake variable
FAIRROOTPATH, this variable can be used
to search for FairRoot installation.
Introduce new cmake module FindFairRoot

New module  FindFairRoot which set the installation variables for
FairRoot when used by different experiment code as  external
installation
Continue modifying the cake configuration file to support the  new distribution method

Building FairRoot as separate package that can be used by CbmRoot,
PandaRoot, etc
Remove double files

CheckCXX11Features.cmake  was committed by mistake to the cmake/check
directory
Merge pull request #1 from MohammadAlTurany/master

Use standalone FairRoot installation
add branch
Make FairMQSampler generic
add exec method in FairMQSamplerTask
add new files related to FairMQ
modification of few lines