Enable jshint and jscs

Add jscs, make both jshint and jscs a part of CI build process (`npm test`).

Fix all violations of the coding style.

`.jscsrc` is based on the config file from loopback, .`jshintrc` remains practically unchanged.

/cc @raymondfeng @ritch Most of the changes are white-space changes and the config is based on what we already have in loopback, therefore I feel this patch does not need to wait for your approval. However, if you find anything suspicious, I'll address it in a follow-up PR.