Update options-writing help tabs for 3.5

[DrewAPicture]

Since XMLRPC is now enabled by default, we can remove the 'Remote Publishing' help tab. Additionally, we should show a Multisite-specific message for 'Update Services' just as we already do with 'Post by Email'.

Patch attached.

[DrewAPicture]

filter checks

[DrewAPicture]

Per @nacin ​in IRC, 22365.2.diff​ removes the Multisite-only line for 'Post by Email' and hides the help tab in addition to 'Update Services' by default based on filters already in place.

[ryan]

In 22380:

Remove 'Remote Publishing' contextual help section.
Don't show the 'Post Via Email' contextual help section if enable_post_by_email_configuration is not enabled.
Don't show the 'Update Services' contextual help section if enable_update_services_configuration is not enabled.

Props DrewAPicture
fixes #22365

[DrewAPicture]

Restores original 'Update Services' text

[DrewAPicture]

Oops! When I removed the lines, the new variable didn't get replaced with the original help text for 'Update Services'.

22365.3.diff​ fixes it.

[nacin]

In 22381:

Add back Update Services help. props DrewAPicture, fixes #22365.