Shorten parts of the quickhelp

Mostly an aesthetic change here
* shortened a couple of the descriptions so everything will fit in less space while still being clear in meaning
* separate binding from descript with a colon, and just separate by spaces.  This is like what is seen on the bottom title bar (except two spaces), and is also reflected in other TUI programs, like mutt.

![Quickhelp](https://i.imgur.com/IWPd0VP.png)
![Quickhelp 2](https://i.imgur.com/Q367QCO.png)