Fix #74: gozmqfix panic under go 1.1

This panic actually occurs whenever gozmqfix is applied to a package
that imports gozmq without an alias, and is not 1.1 specific.
Add basic support for zmq_socket_monitor

Signed-off-by: Ondrej Kupka <ondra.cap@gmail.com>
Add tests for zmq_socket_monitor

Signed-off-by: Ondrej Kupka <ondra.cap@gmail.com>
Make tests compatible with Go version < 1.1

Signed-off-by: Ondrej Kupka <ondra.cap@gmail.com>
Merge pull request #77 from tchap/zmq_socket_monitor

Add basic support for zmq_socket_monitor.
Use C.GoBytes instead of C.memcpy

I noticed that there was memcpy used a few times where C.GoBytes was more
appropriate.

Also remoted a few unnecessary unsafe.Pointer casts.

Signed-off-by: Ondrej Kupka <ondra.cap@gmail.com>
Merge pull request #81 from tchap/use-cgo-calls

Use C.GoBytes instead of C.memcpy
Update godocdown.
Add license link to README.
Travis CI: Use current version of Go

Signed-off-by: Ondrej Kupka <ondra.cap@gmail.com>
Merge pull request #85 from tchap/travis-go-1.1.1

Travis CI: Use current version of Go
Implement zmq_disconnect

Signed-off-by: Ondrej Kupka <ondra.cap@gmail.com>
Merge pull request #89 from tchap/socket-disconnect

Implement zmq_disconnect
Generate SetTCPAcceptFilter(string).
Generate SetROUTERMandatory(bool).
Generate SetXPUBVerbose(bool).
Generate MaxMsgSize().
Generate DelayAttachOnConnect().
Generate IPv4Only().
Add SetTCPAcceptFilterNil.