Update package documentation
Update development and CI configurations

* Use code analisys recipe
* Implement support for Coveralls
Remove dependency with collective.nitf
Change Blog view to display every content type as a blog post, there is some harcoded exceptions (Image, File & Folder)
Blogs can contain every content type but not blogs
Fix blog viewlet
Fix GS type registration
Remove workflow, handle permission in an event
Test subblogs
Test Blog subfolders
Clean unused code.
Fix test_content
Merge branch 'blog_for_all' of github.com:simplesconsultoria/sc.blog into blog_for_all