Adds unit tests and lint

Adds unit tests for primary functions of demeteorizer as well as a
JSHint `pretest` script as part of the build. Adds configuration for
Travis with node versions 0.8 and 0.10 (this will also run builds
for pull requests - yay).

Adds a `.jshintrc` file for future contributors to use when making
changes. :)

Also includes some stylistic changes (normalization of styles, really).

Adds the following dev dependencies:

* sinon@1.10.3
* jshint@2.5.5
* proxyquire@1.0.1
* should@4.0.4