Usability improvements for sliding (channel switcher)

[haarp]

Please don't mind the bug spam, I'm just filing down all the things I've noticed during my usage of HoloIRC (which is a fine client indeed! :) )

The sliding behavior could be improved a bit.

• First off, the input field loses focus when the channel is switched, yet the keyboard is still being displayed. So when the channel is switched and one starts typing, it goes nowhere.
• Secondly, the switching animation tends to be a bit slow. While it looks cool, there is some jarring delay between switching a channel and the actual content fading in.
• The Users and Actions menus have some weird behavior. The Actions button opens and closes the action menu, ok. The Users buttons opens the User menu, but then switches to the Actions menu when pressed again. That's very unintuitive and weird, maybe even a bug? The Users button is probably meant to close the menu again too.
• Lastly, the Users menu could be replaced entirely by having the user list slide in from the right, similar to the channel switcher. Now wouldn't that be cool? :)