Add logging module for node

It's a very basic API for now with support for logging messages to the console and the filesystem.

`logger = require('./logger');`

You then have access to the logger object, which has methods for:

```
info
warn
error
debug
```

You can then use the logger as such:

`logger.debug("My info from module: " + someVar);

The logger has one ENV var constraint. You must set a `LOG_LEVEL` variable to see higher levels of info.

`export LOG_LEVEL=debug`
or
`LOG_LEVEL=debug gulp`