added links to more help on the wiki.
testplan: described the tetraminos and commands to spawn them.
testris: ignore blank lines
Test 4 (io.c) fix

Space character ' ' at wrong location on line 161. Moved to conform with
format of other tests.
rollback of 92f8fde44f

The ';' command is meant to generate a blank line, so matching it
was intentional.
tesplan: finished descriptions, added tests for screenflow and learntris.end, added notes on extending the tests.
fix timeouts on python3