fix % interpolation

it works better when there's actually a `%` there
Merge pull request #42 from tisdall/patch-1

fix % interpolation
Add changelog entry for #42
Strip whitespace around TALES pipes

fixes #43
Tweak extractor API

Only allow classes as extractors, and pass a config-dictionary to them. This allows for per-extension configuration.
Prepare 2.5 release.
Onwards
Fix handling of Babel plugins

We now create a name extractor class for each Babel wrapper. fixes #44
Support per-extractor configuration

In addition also straighten out the terminology: consistently use the term extractor instead of a mix of extractor and plugin.
Make default XML expression engine configurable
Babel plugins return a list of comments

fixes #44
Handle old-style config format for now.
Send warning to stderr.
Add  a separate Zope extractor
Add extractor description.
Document engine changes.
De-dup babel plugin references.
Nitpick
Tweak
Fix typo (stopped by @rnix).