Merge pull request #174 from kigeia/unstable

Separate labels from content for whoosh indexing
correcting a bug introduced by myself during logging implementation
Fix scanning

Signed-off-by: Jerome Flesch <jflesch@gmail.com>
Merge branch 'testing' into unstable
Merge pull request #175 from jaesivsm/unstable

correcting a bug introduced by myself during logging implementation
various fix, another logging implementation (ahem) and a missing import
Merge pull request #176 from jaesivsm/unstable

another logging implementation failure and a missing import
Fix a cache bug on document reexamination
Add label sklearn estimator