Fix bug in assertTableEq and assertTableNe

* Replace code copy and pasted from elsewhere so no longer fails
Provide more insightful messages when tests fail

* Put args of asserteq and asserttableEq as 'expected' and 'actual' format
* Put args of assertTableNe as 'ta' and 'tb', fix error in violation string
Change order of arguments, update documentation
Merge pull request #28 from jagapiou/fixTableEqBug

Fix table eq bug