Notify user during mapping of inconsistent type match

When a user maps two fields that are not of the same type, perhaps it would be useful to notify the user of this before even attempting to run a script. This could help avoid crashes while also making sure the user has double checked the types of their fields.

When two types are mapped to each other that aren't the same type or the same size, perhaps we could put an yellow warning icon in the space noted below with a tool tip warning users of the disparity.