V0.8.0 release

@christian-bromann @camme What do you think?

I rebased the 0.7.14 branch and we should work on 0.8 now.

I refactored a little the test so that we do not require a test runner and we can keep using the standard mocha command line.

Also the tests does not require chai nor any module.exports() wrapping which is simpler.

We should not merge 0.8 right now, here's what's missing:

- [ ] travis ci build
  To simplify things for now and to allow easy local testing. Which is the first thing we should always get from a project so that anyone can participate in it. I had to remove some travis-ci specific code, right now I don't know if it will work. I don't know how to simulate and launch a travis build either.
  We should use a travis.sh build script that will run. Something like:
  ```sh
  BROWSER=chrome VERSION=28 tags= build=.. npm test
  ```
- [ ] `.pause(1)`. It seems @christian-bromann you stumbled on what I call the `fucking pause(1) bug`. There's a bug in the chain API or there's a feature we do not understand that prevents us from removing all pauses. Why would we need to [pause(1)](https://github.com/camme/webdriverjs/blob/ce8b010be5e29ac9ca1eb02b23446127666e7f44/test/spec/windowHandle.js#L97) in some circutance otherwise the chain api stops? I don't know but it's a nasty bug.
- [ ] The promises test is broken, see my comment in it around the [setTimeout](https://github.com/camme/webdriverjs/blob/ce8b010be5e29ac9ca1eb02b23446127666e7f44/test/spec/promises.js#L47), there's no way the chain API will ever know how to deal with such circumstances like an inside setTimeout. Should we support it? I think not.
- [ ] tests for not tested protocol methods
- [ ] maximize window features

Any other feature you want to be included in 0.8.