Begin work on Polonium extra commands

Commands stubbed such as precision and help.
Also alias "exit" for "x"
Whoops. Needed to fix Polonium

Forgot to qualify List with java.util

Now it works correctly.
Exposed the default precision in the Value class, with a get and set.
Value and Polonium extended.
Capable of handling our new Precise numbers.

Yay!
Added Polonium help functionality

also, I can't commit from Eclipse, apparently.
Merge branch 'precise' of https://github.com/ArcticLight/JRPNMachine into precise
Polonium help updated.
Fixed https://github.com/ArcticLight/JRPNMachine/issues/29

Found the bug (missing curly-brace) that was causing issue
https://github.com/ArcticLight/JRPNMachine/issues/29 and resolved it.
Also, added a warning that some operations may be unavailable when
toggling into high-precision mode.
Merge pull request #30 from ArcticLight/precise

precise