plugin(points): +/- must come after, closes #34

plugin(points): +/- must come after, closes #34

This modifies the karma/points plugin to ignore increment/
decrement suffixes. `--SOMETHING` is more trouble than its worth,
people will write --NAME as a signature, or paste a command
line argument, e.g. `ls --sort time` which causes issues.

I also added tests for the points plugin, the plan is
to make the plugin testing easier more "rubionic"