case sensitivity issues

[Dean Gaudet <dg...@arctic.org>]

RFC2068 section 2.1 states: 

   "literal"

       Quotation marks surround literal text. Unless stated otherwise,
       the text is case-insensitive.

Section 3.3 defines acceptable date formats in terms of RFC822,
RFC850, and RFC1123.  None of the latter specify if the date format is
case-sensitive.  But RFC2068 implies here that dates are case-insensitive.
I suspect this is an error, and dates are in fact case-sensitive.
I'm guessing this because Roy built util_date.c and it is definately
case-sensitive.

We do pretty well getting this stuff right... but I fixed a few cases.

mod_rewrite still has problems I think -- in particular it does
strcmp(r->uri, r->main->uri) a whole bunch.  That's not a valid way to
compare two URIs unless it's known that neither have schemes/hostnames.
But I suspect it's not really an issue.

Also, users using mod_rewrite with scheme names in regexes would have
to do [Hh][Tt][Tt][Pp]: in order to match the protocol... things
would probably be much better if we just always ensured the scheme
and hostname were lowercase (and :80 was removed) before doing a
comparison.

Dean