don't like it, but it passes and is consistent...
more attempts at whitespace
whitespace resolved
doctype function fix
rm debug
dict operator access
whitespace
test_example
assert_list
location
added 'location' to PlywoodValue objects, so that errors will be able to be associated with code
added 'slice' operator and value (like List, but can also represent a single value)
renamed 'PlywoodSlice to PlywoodIndices, and added PlywoodSlice, which really is a slice object