Bump version to 0.67

Seems it is stable enough for a release.

Version 0.66

Version bump - 0.65 and update docs.

This version is stable version.

Rewrite the program and drop support to libevent 1.x.

Change version number to 0.51

Version bump - v0.4

Version bump.

README: comment about UDP via OpenSSH & README.html

Release 0.1: TCP, basic UDP, Linux and OpenBSD support.