Improve the usability of activity logs

The UX of the activity logs in Commons is a bit overwhelming at times and provides too much clutter. An example of how it could be improved is by looking at SalesForce Chatter. The main aspects that I took away from my experience are the following:

• The comment textarea is hidden by default which reduces clutter
• The hook_link() equivalents are simple and have small icons to help identify what they do
• Simple button that exposes a popup with help text on how the status streams are used

See the images below for more details: