Cooperator Release

Add mixed strategies (as transforms and meta strategies).

Include a DOI.

Merge pull request #448 from alcarney/gitter-travis-integration

Adding travis notifications to gitter chat

Match class and sparklines

v0.0.21

New release.

Strategies have `makes_use_of` and doc improvements.

v0.0.20

New release.

Efficiency improvements, new default colour maps

v0.0.19

New release.

New strategies

v0.0.18

New release

v0.0.17

Strategy transforms!

Tidying strategies, action classes, flip action method and new docs

v0.0.16

New release.

Distribution of wins plots and more!

v0.0.15

New release

Some bugs and a mirror strategy

v0.0.14

New release