Chat Redesign:
+ New style classes, opening the door to further graphic redesign.
+ Revamping of the user list.
+ Revamping of the input block.
+ Small changes in the messages block, including floating timestamps to the right.
+ Responsive design: use flexbox for chat layout.
+ Responsive design: make user list horizontally scrollable for 'small' widths.
+ Expose user_id in a hidden div, in the chat adp, so it can be used by the javascript part to check and assign different styles to the chat messages if they belong to the user watching the page.
+ xotcl-core: Pass color and user_id in the message, avoiding the creation of the user link at this level.
+ xotcl-core: Remove user_link proc.
+ xowiki: Avoid autocompletion in input field.
+ xowiki: Adding and relocation of div elements.
+ xowiki: Simple function to transform url-like elements of the messages into links.
+ xowiki: Create user links in chat-common.js.
+ xowiki: Check user_id and assign classes to elements depending on the user watching the page.
