plymouth-set-default-theme: Use a more targeted bash ini-parser function...
plymouth-set-default-theme: Use a more targeted bash ini-parser function instead of sed to handle the config file
This is kind of a repurposed and tweaked up function from my waylandloginmanager.
It takes 4 arguments, the file, the ini-section the key name and the new value, if the new value is not set it returns the current value.
Should fix #238 (closed)
Lot of bashism's, but it already is a bash script