updated docs with the changes from Jimmy, see pull request from April 17, 2014
Merge https://github.com/alexlib/openptv-python into alexlib-master

Conflicts:
	docs/install_pyptv_ubuntu.md
	docs/source/index.txt
	docs/source/intro.rst
	docs/source/intro.rst~
	docs/source/tutorial.rst
	docs/source/tutorial.rst~
Merge branch 'alexlib-master' into docs

Conflicts:
	docs/add_docs/PTVFileSystem.pdf
	docs/add_docs/calibTutorial.pdf
	docs/add_docs/ptvmanual.pdf
	docs/add_docs/single_and_multi_plane_calibration_guide.pdf
	docs/build/html/_sources/index.txt
	docs/source/add_soft.txt
	docs/source/index.txt
	docs/source/index.txt.orig~
	docs/source/intro.rst~
	docs/source/tutorial.rst~