Clarified TLS Docs

Made a "Secure by default" section, create 2048-bit keys, various cleanups.

Docker-DCO-1.1-Signed-off-by: Aaron Huslage <huslage@gmail.com> (github: huslage)
Capitalization

Docker-DCO-1.1-Signed-off-by: Aaron Huslage <huslage@gmail.com> (github: huslage)