Update CHANGELOG.md
style(progressCircular): prefix variable names
fix(checkbox): expands the checkbox click radius

Closes #379.
docs(): add two frame delay to highlight code render
fix(checkbox): fixes issue where double-clicking checkboxes causes text selection

Closes #588
docs(guides): fix minor errors and typos
docs(): fix demo-toolbar button color
update(docs): jsdocs for radioGroup

Close #787.
enhance(ripple): adds support for $mdThemingProvider

Closes #748
update(docs): jsdocs for md-text-float

Close #762.
update(docs): rename tab buttons in Source View

Close #827.
update(text-float): updates API docs):

Refs #827.