Updated "easy-rsa" for OpenSSL 1.0.0

Updated "easy-rsa" for OpenSSL 1.0.0

This patch fixes remaining issues with Trac ticket #125. It does the following:

- Update easy-rsa/2.0/README
- Rename easy-rsa/2.0/openssl.cnf as openssl-0.9.8.cnf
- Add easy-rsa/2.0/openssl-1.0.0.cnf
- Updated vars.bat.sample to use openssl-1.0.0.cnf
- Updated win/openvpn.nsi to use openssl-1.0.0.cnf
- Add a few undefined variables to vars and vars.bat.sample:
  required by OpenSSL 1.0.0 (at least on Windows)

Signed-off-by: Samuli Seppänen <samuli@openvpn.net>
Tested-by: Samuli Seppänen <samuli@openvpn.net>
Acked-by: David Sommerseth <davids@redhat.com>
Signed-off-by: David Sommerseth <davids@redhat.com>