Added the environment variable HUBOT_SKYPE_ADAPTER_PYTHON for a custom location of the python executable

Signed-off-by: Philipp Beckmann <philippbeckmann@pabnet.de>
Update src/skype.coffee

Renamed env var to HUBOT_SKYPE_PYTHON to match existing vars
Stop repeating yourself hubot.
OSX 64-bit no longer crashes, but instead refuses to start 

Fixed Skype4Py https://github.com/awahlig/skype4py/commit/95a36c95043697e91bd139c269cd1d428e29327a
updated deprecated functions
fixed Skype4Py name
Merge pull request #23 from yokomizor/fixed_skype4py_name

fixed Skype4Py name in readme
Merge pull request #20 from miohtama/master

Updated README regarding Skype4Py and OSX crash
Merge pull request #22 from yokomizor/updated_deprecated_functions

updated deprecated functions
Merge pull request #18 from savagegus/master

Hubot replies to himself
Merge pull request #14 from philippbeckmann/Branch_envvar

Environment variable for custom location of the python executable