bash: rain: add vnet alias
makepkg: stop trying to use ccache

gtk3:
 - With ccache: 6m18s first, 3m11s second
 - Without ccache: 5m21s
makepkg: do not build with -g by default

The debug symbols grow gtk3 from 5.7 MB to ~27 MB.

But on the second thought, maybe I should set this per-package (in
gtk3/PKGBUILD and such), because the size difference isn't large for
programs; e.g. ~2 MB for mutter. Or I could add the (strip) option for
gtk3 only.
ssh: hosts (+ ukolegija)
bash: rain: add missing `sudo`