Support node color and icon options

[kazuhitoyokoi]

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)

Proposed changes

To support --color and --icon options for command line, I added the source code.
Using these options, node developers can directly specify node color and icon without modifying node's html files manually.

Checklist

• I have read the contribution guidelines
• For non-bugfix PRs, I have discussed this change on the mailing list/slack team.
• I have run grunt to verify the unit tests pass
• I have added suitable unit tests to cover the new/changed functionality

[coveralls]

Coverage decreased (-2.0%) to 65.26% when pulling 1099ea7 on kazuhitoyokoi:master-supportcoloriconoptions into aabec5a on node-red:master.