#748 Put a checkmark only on the subscribed plan

Before there were checkmarks on every plan, even though you weren’t
subscribed to them. Those have been removed. Also, I’ve removed the
“subscribed” text from inside a button to just plain, then styled it.
Fix + improve selected message on subscribed plan
Merge pull request #278 from lachlanjc/wip-748

#748 Put a checkmark only on the subscribed plan