bashrc: Remove lock(), add as script instead

I just named it /usr/bin/lock instead, so that it can be run through
dmenu

Signed-off-by: Carl Helmertz <chelmertz@op5.com>
screenlayout: A single screen

Signed-off-by: Carl Helmertz <chelmertz@op5.com>
i3: mod+space: app launcher, resize with vim keys

The resizing also had an offset of one key to the right.

Signed-off-by: Carl Helmertz <chelmertz@op5.com>