4.0.0 beta.4: Misc tweaks based on testing at BS01

Misc tweaks based on several months of use on biosector01.com:

• Adjust avatar markup for easier customization using strictly CSS (instead of using Refreshed-icon-logged-* system messages). Use case: adjusting avatar based on theme (e.g., on BS01, Refreshed light and dark modes have different logged-in avatars)
• Move main title messages for better title wrapping when page indicators are wide
• Fix issue where dropdown would not close
• Remove JS that was already commented out

Since BS01 has used this skin without issue for several months now (and the skin has held its own when put through substantial CSS customization) I'm fairly confident this is stable enough for production now. Potential tweaks:

• A way to add custom LESS rules without using an extension? (A custom LESS file in the styles directory that is listed in .gitignore?)
• ResourceLoader integration so other extensions (e.g., Extension:Theme) can rely on Refreshed-specific mixins
• Replace the "icon dump" at the top of RefreshedTemplate.php with something more elegant

Change-Id: Ib47567415a7e9a67d8f54fbf43408e46012d6326