Cleanup
Do not store dependency flags

These are never used and are not exported
Print warning to remember to update when we change cmake minimum required version
Install Allegro bindings using relative path
Fix stage module build
Clean and improve FindFTDI and move it in conf folder
Clean and improve FindFFMPEG
Clean and improve FindPortAudio
Clean and improve FindStage and move it in conf folder
Add FindFreenect module
Add FindLibUsb1 module
Add FindOpenNI module
Remove YARP_ADMIN environment variable

It has been deprecated since January 2013
Update CMake upstream modules

* Updated modules:
  - FindFreetype.cmake
  - FindGTK2.cmake
  - FindPackageMessage.cmake
  - GNUInstallDirs.cmake

* New modules:
  - CMakePackageConfigHelpers.cmake
  - FeatureSummary.cmake

* Update Copyright.txt

* Moved to conf/cmake-3.1

* Installed in ${YARP_MODULE_DIR}/cmake-3.1/Modules

* Latest revision: 0a64c48d3852010341d09c0c18fc0c0d88e1b48e
Merge branch 'cleanup'