gofmt changes only.
Fix stack overflow bug.

runtime: goroutine stack exceeds 1000000000-byte limit
fatal error: stack overflow

runtime stack:
runtime.throw(0x745840)
        /usr/lib/go/src/pkg/runtime/panic.c:464 +0x69
runtime.newstack()
        /usr/lib/go/src/pkg/runtime/stack.c:295 +0x3bc
runtime.morestack()
        /usr/lib/go/src/pkg/runtime/asm_amd64.s:225 +0x61
Add helper method which can create an Error object from an IB ErrorMessage.
Change test to use AUDUSD to ensure better coverage if not subscribed to
US markets.
Fix engine_test logging bug where reply was nil.
Enhance bidirectional traffic dumping between IB Gateway and Go.
Ignore test binaries.
Send IB ErrorMessage events to the error channel.