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
rename splitter/merger to shorter/generic names
add cmake module to find nanomsg
a little clean up
add files for interface implementations
add build and data directories to gitignore
let cmake nanomsg finder recognize platform
correct a typo
beautiful defines match class names
add macro to start three devices
fix a typo
add factory classes
use factory for sockets
use factory for messages
get rid of unused function warning, no need for static.
rename fTask to fProcessorTask for clarity and to resemble fSamplerTask name