Make show list in act submit dynamically settable

[bethlakshmi]

I have gbetext.py hard coding the show preferences that show up in the act submit and the act filter.
That's fussy and bad practice and makes one more thing that has to be done every year by a SW person.

Minimum - change the list to a value in our DB that anyone with admin privs can edit.
Better - may be to offer the list as a dyamically insertable value that Scratch can use a bunch of places in our content so he doesn't have to rewrite stuff all the time. But that's a bonus and only if it's actually useful.

[bethlakshmi]

Another bit of info - this causes confusion for act coordinators, since they think that because this list is ready, the show-casting is ready.