Problem: artificial restriction on binary identities

Applications that use ZMQ_IDENTITY can be trapped by the artificial
restriction on not using a binary zero as first byte. It's specially
nasty on random generated identities, e.g. UUIDs, as the chance of a
binary zero is low, so it will pass 255 out of 256 times.

Solution: remove the restriction.
Whitespace fixes
Use different endpoint for each test step
Don't reconnect on protocol errors
Merge pull request #1037 from hintjens/master

Problem: artificial restriction on binary identities
Merge pull request #1042 from hurtonm/master

Fix bug in reporting protocol errors
Merge pull request #1043 from hurtonm/dont_reconnect_on_protocol_errors

Don't reconnect on protocol errors
Add a send timeout in expect_bounce_fail() so tests for authentication
failures don't block.
Set an alarm(60) in setup_test_environment() when not on windows so tests
will not block too long if they go wrong.
Merge pull request #1046 from mrvn/pull-testutil-set-alarm

Set an alarm(60) in setup_test_environment() when not on windows so test...
Merge pull request #1047 from mrvn/pull-testutil-expect_bounce_fail-send-timeout

Add a send timeout in expect_bounce_fail()
PLAIN: Small simplification