Fix Python calls to dict().
Fix calls to float(), str(), tuple(), list(), and dict() with no arguments.
Implement zip.
float() should only accept string or number.
Do not mask errors on invalid falsy arguments.
Fix sum().
Fix tuple().
In list() set __class__ of object.
Simple equality test.
math.log with a base, math.log10, and math.trunc
Add random.choice
Make % operator match Python for all cases a/b positive/negative.
Fix string.capitalize().
Possibly incorrect truncation before converting to biginteger.
Fix range.  It is not the same as extended slices.
Make exception message match Python.
Merge branch 'master' of ssh://orion.cs.rice.edu//home/rixner/git/skulpt.fork
Revert "Possibly incorrect truncation before converting to biginteger."

It was incorrect.

This reverts commit 68095c80848ce9da598e716a9b45a063ca09af34.
Check that compiler generated functions are called with the correct
number of arguments.
Handle kwarg a little better.