Add documentation for "MDCACertificateFile" on httpd.apache.org

[mkauf]

I have learned about the directive MDCACertificateFile in issue #361. It's very useful, please document it on https://httpd.apache.org/docs/2.4/en/mod/mod_md.html .

This directive is already documented in README.md, but it's missing in the Directives overview.

Additional documentation issues in README.md

These directives are missing in the Directives overview:

• MDBaseServer
• MDCACertificateFile
• MDContactEmail
• MDExternalAccountBinding
• MDMustStaple
• MDProfile
• MDProfileMandatory
• MDRequireHttps
• MDRetryFailover
• MDStoreLocks

These directives are not documented in README.md, but they are documented on httpd.apache.org:

• MDActivationDelay
• MDCertificateCheck
• MDDriveMode

Additional documentation issues on httpd.apache.org

Documentation error for MDCertificateCheck: "Set name and URL pattern for a certificate monitoring sitSet name and URL pattern for a certificate monitoring sitee"

[icing]

I added the directives missing in the link list and a description of MDCertificateCheck in #368.

Regarding other 2 directives mentioned in the Apache documentation:

• MDDriveMode has been renamed to MDRenewMode. It is in the code only for backward compatibility. The Apache doc mentions this. I do not want to list it in the README since it shall no longer be used.
• MDActivationDelay: I no longer think this directive is a good idea. It is faulty. The delay does not prevent the activation on a server reload/restart. It merely delays the "this is now ready" event. This is weak and can be confusing. I think it needs to go, e.g. become an invisible NOP.

[mkauf]

Thank you, I think the directives documentation in README.md is now in a good shape.

Can you please also add documentation for MDCACertificateFile and fix the documentation for MDCertificateCheck on https://httpd.apache.org/docs/2.4/en/mod/mod_md.html , or is https://bz.apache.org/bugzilla/ the correct place to report that?