testutils: fix undefined variable in packet_in_match
testutils: add new functions to check for dataplane packets

`receive_pkt_check` and `receive_pkt_verify` had slightly different
functionality and neither were sufficient for complex tests. This change
deprecates them and adds new functions.

The high level `verify_packets` function is sufficient for most tests. When
more complex logic is needed the primitive functions `verify_packet`,
`verify_no_packet`, and `verify_no_other_packets` should be used directly.

All OpenFlow 1.0/1.3 tests are updated to use the new functions. The old
functions are left around for compatibility with out of tree tests.
testutils: use idiomatic ternary operator in flow match tests functions
Merge into master from pull request #70:
testutils improvements (https://github.com/floodlight/oftest/pull/70)