basic_headers no longer combines fields with the same name by appending
a comma and concatenating the two values together. This was breaking
certain header fields which expect each value to be distinct, such as
the "Set-Cookie" header.
Now the container behaves more like a multi set with respect to insertion
of multiple values with the same field name. Additional member functions
are provided to provide extra functionality.
ext_list:
Iterable container of comma separated extensions, where each extension
is a token followed an optional list of semicolon delimited parameters,
with each parameter consisting of a name / value pair. The value can
be a token or quoted-string.
param_list:
Iterable container of semicolon delimited parameters, where each parameter
is a name / value pair. The value can be a token or quoted-string.
token_list
Iterable container of comma delimited tokens.
* Remove obsolete rfc2616 functions
* Refactor and consolidate case-insensitive string helpers
