read booleans from config and fix spanning monitors

[jegeland]

• Cherry-picked several doc cleanup commits from upstream.
• Fixed boolean vars in config not being respected
• Made the hidden banner timeout configurable
• Fixed spanning the banners over multiple monitors

Tested and validated on Centos 7.9 with kernel 3.10.0-1160.71.1.el7.x86_64

[redhatrises]

lgtm

[jegeland]

@redhatrises Thanks! I realize I didn't put my name in alphabetical order in the Contributors.md 😞 Sorry about that