Icons for lead entity types

[seriousben]

We should be able to represent the lead entity types like the Goals themselves that is with icons.

At least we should get rid of the list for entity types since there is only 11 lead entity types anyway.

[rjriel]

I think that the ability to filter by lead entity types is beneficial and important, but I do agree that since there is a small finite list that being able to represent them like the Goal 14 targets would be awesome.

Any UX type people willing to take a crack at coming up with some icons for this? @5o5?