Prepare for first release

[mucaho]

The basics should work, see mucaho/wdio-qunit-sample for a working integration example.

• Add appropriate topics in the repository description, similar to mucaho/wdio-qunit-framework
• Enable travis for this repository and add appropriate badge from travis build
• Merge in necessary functionality in wdio-sync:
  • Let runInFiberContext wrap non-global functions wdio-sync#58
  • Call specFn and hookFn with received arguments wdio-sync#59
  • adjust wdio-sync devDependency once that version of wdio-sync is on npm
• Enable rewire babel plugin and apply workaround for current bug, see TypeError: _get__(...).__REWIRE__ is not a function speedskater/babel-plugin-rewire#109
  enabled via 579539b, the problem was a rewired dependency was imported in a test, but not used
• Fix reporting of tests
  fixed via 5e654af, test:pass/test:fail events are necessary to be broadcast too
• Add tests, adapt them from e.g. webdriverio/wdio-mocha-framework

Optional things to include in first release, but could be postponed to next one

• Enable test coverage, add badge, see webdriverio/wdio-mocha-framework
• Enable static code analysis (codeclimate), add badge, see webdriverio/wdio-mocha-framework
• Enable dependency tracker (versioneye), add badge, see webdriverio/wdio-mocha-framework