Merge branch 'release/2.3.1'
Merge branch 'release/2.3.2'
Merge branch 'release/2.3.3'
Merge branch 'development'
Added icon and class, clean code
Added title to button (allow tooltip), fixed bug on groupedbutton
Refactorise parseFieldTags
Added checkboxes form field
Documentation update
Merge pull request #418 from Eighke/tmp

Form fields update
Fix calculating the default layout name
Merge pull request #419 from akeeba/feature/fix-layout

Fix calculating the default layout name
Docblock
Merge branch 'master' into development