Add variable for creating dynamic paths

Setup a variable and instructions that would allow paths to be stored in Flashlight, rather than manually setup in the config file.
Monitor paths specified in Firebase

Look for path objects that have been stored in Firebase, and monitor them (based on path set in config.js)
Pass FB_PATHS to process method

Sends the FB_PATHS variable from config.js to the PathMonitor process.
Update app.js
Default paths to null, rather than location
Merge pull request #10 from hsubu/patch-2

Allow paths to monitor to be specified in Firebase