New load balance strategy: latency.

Select proxy with lowest connection latency.
Use Go 1.3 for Travis CI.
Sleep on error in accept loop.

Avoid flood of error logs upon too many open file error on Linux.
Get install directory from environment variable.
Bump version to 0.9.2
Allow @ and : inside password.
Merge remote-tracking branch 'upstream/develop' into dev

Conflicts:
	README.md
	parent_proxy.go