Turn on spell checking for all files by default.
Enable camel recognition for spell checking by default.
Remove no longer used files as they only turned spell checking off,
which no longer is necessary.
Add for PHP via existing phpactor as server.
Use new signature plugin for proper none irritating inline help during
function calls.
TODO: Get rid of preview window showing up …
This eases maintenance as I don't need to commit and push one repo, and
update rev and sha in here.
Instead I can just change configuration and run home-manager switch.