Template can now track it's implementations.
When you re-save the template, it'll grab it from the previous configuration.
Eventually implementations will register themselves with their templates.
changing it to a set
refactoring the code that finds the project in the request into a utility method
Display all implementors in the template property
adding add/remove implementation methods
implementations now register and deregister themselves with their templates.
wrapping in entry tags so that it appears inline rather than at the top.
only log when there's something to log about
use a threadsafe Set
Save the template's job when an implementation updates the implementation set.
implementation should save templates only when it actually modifies it.
Saving the template will now save all it's implementations.
log a warning when we remove.