Add -keyfile=*.pfx

Add list of Subject components

Adjust openvpn suggestion

Shellcheck complaints

Shellcheck tweaks

Small change for codesign certificates

Allow -cn= option to be blank

Add Install instructions

Change whatssl for new version of openssl verify.

Reduce the default period for DV certs to 398 days.

Hiding various shell-check things

Improve -days option to include explicit end date (ISO format)

Add Travis CI and testrun.sh

Simplify caname option.

Small cleanup on help text