Support for Page Up and Page Down keys in Branchlist

[nheilbuth]

Would be nice to be able to scroll long lists (ie. branches list) using page up/down instead of just arrow keys

[extrawurst]

good point, it is missing on the branchlist. let me know where you miss it aswell

[nheilbuth]

Just noticed that pgUp/Down support is also missing in the files list when inspecting a commit
(go to log, select a commit, press right arrow to inspect).