[GTKUI] Add associate magnet reg in Windows
[GTKUI] Allow the Tabs area to be resized smaller

 * Tabs can now be scrolled if too many for height.
 * Change window_pane_position default to 235, based on default 480 window height.
 * Set the vpaned size before show call.
 * Reduce top padding and set bottom padding to 2, to account for decender letters.
[Extractor] Fix absolute/relative import
Fix RTD badge in readme
Update headers and isort imports
More fixes for previously overzealous changes to setup.py
Correction for Flake8 func rename in log.py

Broke the retrieval of logging lines.
[GTKUI] Fix magnet association button on Windows
Merge branch 'Feature/win32_associate_magnet' into develop
[Extractor] Add Finding Win 7z Path via Registry
Fixes for building docs
Added .travis.yml (for travis-ci) and tox.ini files

Targets:

* Runs the unit-tests for python 2.7
* Tests unit-test coverage
* Try to build docs
* Code style checks:
  * flake8
  * isort

Codes changes:
* Fixed tests for httpdownloader (using tmp dir)
* Implemented a couple of tests for Stats plugin but they fail to run on travis

Issues:
* Can't get py26 to work because of installing libtorrent through apt and
  the option system_site_packages fails for 2.6.
Disable plugins test due to Travis issue

An unknown issue with running the Stats plugins test on travis means it
never passes.
Small fixes for Travis and isort
[Docs] More fixes for testing with tox
Added mock to libtorrent to build docs without libtorrent.

* Added settings for isort to handle third party libraries that aren't installed.