Removing option to have a "short form" address. Deprecating filter pmpro_longform_address

[kimcoleman]

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Changes proposed in this Pull Request:

Removing the filter to disable long form addresses. We will always show the address fields like this and rather use CSS to adjust the appearance of fields.

Other information:

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Changelog entry

• DEPRECATED: Deprecated filter pmpro_longform_address. Address fields will always be shown in longform format.

[kimcoleman]

@dparker1005 resolved merge conflicts in this one.