Manifest timestamp based on maximum file mtime in root directory

In debug mode, recalculate on every manifest fetch
In release mode, calculate at configuration time

Note: in heroku the mtimes will get bumped on every deploy
Merge pull request #2 from cjbest/manifest-timestamp

Manifest timestamp based on maximum file mtime in root directory
cleanup lastModTime fix for multi-instance code
ensure only Date or undefined is returned by modTime updater
HAS_MANIFEST var must be initialised before use
print referrer in logs
dont log heavily in production mode (presumably behind a load balancer who will log)
explicit dependencies
manifest concat line index bugfix. reduce request timeout from 2m to 25s.
manage request timeout without destroying socket (for reuse)
looser script tag matching
-l for awesome logging
queue + pipe logs
window redirect loop bugfix. ignore all invisible files (recursively). concise logging by default.
verbose logging mode
compiled out debug js code
concat accepts zerver scripts
full logging in production mode if verbosity set
forgot to increment version in package.json
concat files with new line