Getting ready to release v9.9.2

First release after splitting it out from OpenVPN.

This release mainly contains a major overhaul of the build tool
chain and will be shipped as part of OpenVPN v2.3_alpha2.

This is the OpenVPN git tree after all files which is not related to

the Windows TAP driver is removed.

This git tree contains the complete history of OpenVPN until the split
of the unified OpenVPN source code repository into the core OpenVPN
part, easy-rsa and the Windows TAP driver.