PyTest: add testProperties

* Contains 2 nose-tests:
     * testAddMetadataDate: add metadata 'date' to the outputFile.
     * testAddMetadataPlo: check if metadata 'plop' is not added to the
outputFile.
PyTest: add testTranscoder for dummy/rewrap/transcode

* Add 6 nose-tests about dummy.
* Add 2 nose-tests about rewrap.
* Add 6 nose-tests about transcode.
Merge branch 'master' of https://github.com/avTranscoder/avTranscoder into dev_pyTest
Swig: rename AvTranscoder to avtranscoder

* Modules are in lower cases (python...).
* Install python module in site-packages/pyAvTranscoder directory.
* Update import of avtranscoder module for pyTests.
Swig python: install __init__.py file
Swig python: fix library name

For Python binding, need to compile the wrapper into a lib called
_<module_name>.so
pyTest testProperties: fit to new API

ProgressListener to NoDisplayProgress.
pyTest testProperties: clean tests

* Create a tuple which can be use after in the assert.
* Rename testAddMetadataPlop to testAddImpossibleMetadata (update
comment).
pyTest testTranscoderDummy: fit to new API

ProgressListener to NoDisplayProgress.
pyTest testTranscoderRewrap: fit to new API

ProgressListener to NoDisplayProgress.
pyTest testTranscoderTranscode: fit to new API

ProgressListener to NoDisplayProgress.
pyTest: use environment variables to use files in tests

Two variables are used in tests:
     * AVTRANSCODER_TEST_AUDIO_FILE
     * AVTRANSCODER_TEST_VIDEO_FILE
pyTest: comment tests which failed

* Temporary solution, to launch tests with Travis.
Update README: add Tests section
Update README: remove Requirements section
pyTest testTranscoderTranscode: add testTranscodeYUV420

Comment this test because of a crash (due to pixel format YUV420).
pyTest testTranscoderDummy: clean tests

Remove spaces and semicolons.
Travis: launch python nosetests after build
pyTest testTranscoderRewrap: remove setProcessMethod

By default the transcoder has process method set to
eProcessMethodLongest.
Merge branch 'master' of https://github.com/avTranscoder/avTranscoder into dev_pyTest

Conflicts:
	src/CMakeLists.txt