Added "by name" capacity to Variables.
Eliminated traceRules from BasicAtom and replaced it with the "rewrite" debug token.
Added "by name" variables to Elision.  Still needed in the packrat parser.
Updates to the documentation.  Still much more to do, but have started the rules and strategies section.
Added is_constant to Core.eli.
Added integer math operations, and renamed some operations to start with an i for integer.
Corrected bug in declaring rules that require completion.  The issue was a problem with handling #ruleset versus #rulesets when interpreting the content of a SpecialFormHolder to create the RewriteRule.
Merge pull request #144 from sprowell/master

Updated documentation and fixed bug in rule completion.