feat(dx): conditional query by unicode value

depending on whether plone.app.contenttypes is there.
changelog
Feature: Add a new widget : BooleanWidget
We get a checkbox widget to filter contents
which gets a true boolean value for an index (FieldIndex or
BooleanIndex).
Update eea.po
remove tabs
Bug fix: fix import of '0' values for boolean properties
which were considered as True when.
Merge pull request #11 from collective/boolean-widget

Boolean widget
Merge pull request #10 from starzel/unicode_index

feat(dx): conditionally query by unicode value
Update Traditional Chinese Message Translation.
[JENKINS] - Fix tests, pylint and pyflakes warnings
typo
avoid logging an error if value is just empty
Merge branch 'master' of git@github.com:collective/eea.facetednavigation.git
Fix field default value rendering with chameleon.
default name is in the scope of widget template and is read only, and default value remains None when defined. This may be a chameleon bug.