removed .gitignore (not needed with catkin)
amcl: changed file layout, exposed libraries and include path
Dependent packages will be able to use amcl as a C++ library this way
calibration: install libs & headers
Merge pull request #37 from dgossow/hydro-devel

amcl refactoring & expose c++ library
Merge remote-tracking branch 'ros/hydro-devel' into hydro-devel