Add cmd-line help and reduce node error output by default

Added nopt package dependency - npm update required!

Added -v cmdline option to show node module load errors, which are otherwise hidden by default with only a summary shown
Tidy up nodes module exports
HTTP In help text should use httpNodeRoot
Add headless mode
closes #2

httpAdminRoot / httpNodeRoot can be set to false to disable their respective bits. If both are set to false, (or httpRoot is set to false), and httpStatic is not defined, then it will not start the http server.
Remove console.log debug
Tiny change to presets for range node - more useful example irl.
Unexpected error if uiPort already in use
Clear palette filter box on reload (firefox)
TCP Node port in use not caught properly
Hide palette until nodes loaded
Skip non-existent node directories
Fix snap-to-grid
Fixes #177
Fix for IMAP node - inbox 0 error.
fix delay node name when using random setting
Add explicit CLA links
Merge pull request #183 from hardillb/master

fix delay node name when using random setting
UDP node fixes. Allow fixing of outbound port.
Fixes #178
Also fixed multicast binding to work more correctly.
Note: - if you fix the outbound port it will then be unvailable for input - as we are not setting up a pool.
tweak "leave blank for random" text for outgoing port
as per Nick's suggestion
Node defaults of 0 not showing in edit form
Fixes #186
Fix config node usage counts