Exchange related tests, restructure of framework

Added several tests to check the impact and interference of commands on the
token and traditional exchange. Furthermore the test framework itself was
partially restructured. This includes reordering the README and refined test
result reporting.
Test "cancel-pair" command and orderbook lookups

Tests creation of several offers and cancellation with the "cancel-pair"
command as well as the appearance of offers in the orderbook provided by
RPC call getorderbook_MP.

Tests passed with Master Core,
Commit: 4c3f204401a5e2592912907365f6fc8e2870beb0

Test log:
https://gist.githubusercontent.com/dexX7/22c05a1b48f3a35b8fd2/raw/