Complete rewrite of the hobby module to be more robust and versatile.
Based on better understanding.

Robustness was gained by basing some of the calculations on the polar
form of the vectors. This makes calculations possible where before
NaN was the result.

Also, new apis based on polar coordinates where established and the
naming of the methods was overhauled.
Basic actions are:
 * tension2magnitude
 * magnitude2tension
 * tension2control
 * control2tension

 Please enter the commit message for your changes. Lines starting
changes according to comments of @rrthomas
Merge pull request #229 from graphicore/redo-math-hobby

Complete rewrite of the hobby module to be more robust and versatile.
Make internal and external names of module match
Merge pull request #231 from rrthomas/master

Make internal and external names of module match
Remove bogus anchor from URL
Merge pull request #232 from rrthomas/master

Remove bogus anchor from URL
Fix red-pill when given no command-line argument

Was using the undefined argument rather than the defaulted
project.dirName
Rename clearPath to cleanPath and shorten

Use path.normalize
Capitalize an HTTP method in a comment
Merge pull request #234 from rrthomas/master

Fix red-pill when no UFO passed on command line
Remove unneeded punctuation and space
Merge pull request #235 from rrthomas/master

Remove unneeded punctuation and space
Add script to run demo CLI session and capture its output
Merge pull request #236 from rrthomas/master

Add script to run demo CLI session and capture its output. Closes #175.
Make script properly idempotent, not raise an error

This eases Vagrant provisioning, as the script can be run without
worrying about it erroring out if there’s already a metapolator
checkout.

Also remove recommendation of hub, that is already in the Vagrantfile.
Merge pull request #237 from rrthomas/master

Make script properly idempotent, not raise an error
Add command description (if any) to usage
Make command summary help available in individual command help

Fixes #223.
Merge pull request #238 from rrthomas/master

Fix #223: make command description available in individual commands’ help