Default to plain/text lexer

Because pygments is somehow always guessing wrong, using x-cdhr or
whatever when trying to guess based on the content of the file.
This will redirect the web ui after submit

Pasting from the command line will behave as usual, pasting from the web
ui will redirect after new post.
Release new version
Merge branch 'master' into production

Conflicts:
	pasttle/__init__.py