Add 'spring test [files]' command to compile and test code automatically

- Look for JUnit test symbols, and add JUnit automatically
- Look for Spock test symbols, and add Spock automatically
- Based on what test libraries were used, invoke relevant embedded testers
  and accumulate results
- Make it so that multiple testers can be invoked through a single 'test' command
- Print out total results and write out detailed trace errors in results.txt
- Update based on the new artifact resolution mechanism
Clean up TestCommand paraphenalia
Refactor cli properties into single project
Add README to cli
Added simple error hangling to 'SnakeTimer#broadcast'

In some cases the websocket communication fails and Snake#sendMessage throws an exception.
In that case the send loop is interrupted and later clients are not update.
Implemented the error handling in case of commucation failures
Add Spring Mobile Device Resolver autoconfiguration
Adapt device change to new springcli.properties
Fix build
Polish CLI tester code

Reduce duplication by extracting FileOptions class to be shared by
both the RunCommand and the TestCommand.

Also applied minor code convention tweaks.
Apply source formatting to samples
Polish

Minor formatting and consistent copyright header.
Polish
Update M4->M5 in README
Use simplified @Grab where possible
Add explicit header link
Update homebrew location
Remove missing links
Fix paragraphs that ran together
Allow user to override static resource handler mappings

A new API in Spring allows us to check for existing mappings in the
resource handler registry