Merge pull request #1 from rattboi/master

Fix multiply's identity function
Added a couple more tests
Merge branch 'master' of github.com:vernonrj/freezing-octo-dubstep
Updated mul unit tests to use identity func
Merge pull request #2 from rattboi/master

Fixed sub arity 0 and 1, fixed tests
Merge pull request #3 from rattboi/master

Added div function, changed plus to add
Merged changes, added concat