xmpp/compress d---------
compress: lowercase error strings

Signed-off-by: Sam Whited <sam@samwhited.com>
all: change stream feature Parse signature

This is a breaking change that makes the function signature of the Parse
function on StreamFeatures actually do what everyone is going to
immediately do with it anyways.

It also fixes the API to make it clear that we're passing a Decoder
which we had to do anyways because if we passed a wrapped TokenReader
and the user created a new decoder from that it wouldn't have had the
start element that we pass in popped from it and would error on reachign
its end element. This wasn't happening only because we were passing the
Decoder anyways and the NewTokenDecoder function would return the
original if the TokenReader was already a Decoder.

Signed-off-by: Sam Whited <sam@samwhited.com>
compress: add security warning to docs

The compression standard may be insecure without taking special care to
flush the dictionary on stanza boundaries.  This must be done on both
the client and the server, and means that compression can't be used
safely unless all implementations behave correctly.  Because of this,
add a warning in the documentation to try and discourage use of this
all: add new API to make reading tokens safer
all: bump to new xmlstream and fix flushing
Revert "all: new session XML read/write API"

This reverts commit 5265955b9c79963ea0c1b9f392db0e56b6a242a8.
compress: remove TODO

[ci skip]
all: new session XML read/write API
all: update copyright message

[ci skip]
all: rewrap copyright comments/use xml.TokenReader
all: use xmlstream.TokenWriter in features

Fixes #39
all: make *Session an xml.TokenReader

This is less efficient than returning one when wraping it in an
xml.Decoder because the underlying decoder cannot be used, but it makes
the API nicer to use.
compress: minor clarifying space in docs

[ci skip]
all: use xmlstream.TokenReader

See #14
compress: add canonical import path
stream: rename streamerror package to stream
compress: Add support for LZW stream compression

Also tweak some comments to make later diffs smaller.

Fixes #15
Make NS autocompletion easier in compression
compress: Fix feature to use an io.ReadWriter