Allow backends to take arbitary arguments.
Merge pull request #22 from ant1441/backend-args

Allow backends to take arbitary arguments.
Fixed bug with exact finder
Merge pull request #23 from jb098/dev

Fixed bug with exact finder
Create Xvfb with a default size
Merge pull request #24 from ant1441/xvfb_default_size

Create Xvfb with a default size
If we don't get a display_num in Xvfb, find a suitable one
Add logging to backend creation
Merge pull request #25 from ant1441/xvfb-auto-file

Xvfb auto file
Add travis-ci config & fix dep versions
Merge pull request #26 from ant1441/travis-ci

Add travis-ci config & fix dep versions
Rename .travis.yaml to .travis.yml
Update .travis.yml
Update .travis.yml

single line scripts
tmp strip out version numbers for travis
run tests differently
Add travis button
Add further filter tests
Add test for colour
Tests for location