[TiddlyWeb] Include both user and mime type info in tiddler and tiddlers ETags

[cdent]

Recently a change was made to include mime-type, but recent email has made it clear that user info needs to be included too. This makes for sad pandas but oh well.

The email:  http://groups.google.com/group/tiddlyweb/msg/2d25932301ccc36a

The expected solution is to make a hash of mime-type and the current usersignname?. Handling of PUT will still just look at the first half (pre ;) part of a PUT If-Match value.

[cdent]

fixed