* Stageless payloads weren't adding brackets around IPv6 hosts.
* Staged HTTP handler was using an undefined function to check for IPv6
addresses when host header overriding was disabled.
Methods now require a hash. I went with the hash because 1) that's what
we seem to use everywhere else, and 2) I couldn't get the new keyword
arguments working nicely with the block syntax (I'm clearly stupid).
Somehow this made it into a merge when it shouldn't have. This fix moves
the URI checksum module to where it needs to be and updates all the
references where required. This will result in a class with the dynamic
transport branch, but I can fix that after.
This fixes a huge number of hard-to-detect runtime bugs
that occur when a default utf-8 string from one of these
libraries is passed into a method expecting ascii-8bit
OJ