Continue work on Apache multivhost
Continue work on Apache multivhost

* Apache: do not assume directives will be CamelCased

* Fixup

* Elaborate

* Simplify the definition of vh_p

jsha/letsencrypt,jsha/letsencrypt,stweil/letsencrypt,letsencrypt/letsencrypt,letsencrypt/letsencrypt,lmcro/letsencrypt,lmcro/letsencrypt,stweil/letsencrypt