Make an option to disable tab switch animations.

I bet I'm not the one driven crazy by them. So let's keep the bling by
default, but make it possible to override that.

In this patch I also sugest usage of tooltips on the config knobs.
How do you like it?
preview: add support for TGV.
Revert "Make an option to disable tab switch animations."

This reverts commit 1d689839c065964333cd2ee8f3e6573b1f38a020.
Make zero-time switches between tabs flick-less.
Let our size spinners be editable.
Make term switching cyclic.

The behavior for tab splits is kinda funky (it's kept equal after my
commit) -- one returns to the last or 1st term of the split, when
cycling reaches it, not the split it was in at the last time.
add some doc about RM 34/36
save wrapnext when saving cursor. Closes T1080