[analyzer] Change the default output type to PD_TEXT_MINIMAL in the frontend,...

[analyzer] Change the default output type to PD_TEXT_MINIMAL in the frontend, error if an output loc is missing for PathDiagConsumers that need it

The title and the included test file sums everything up -- the only thing I'm
mildly afraid of is whether anyone actually depends on the weird behavior of
HTMLDiagnostics pretending to be TextDiagnostics if an output directory is not
supplied. If it is, I guess we would need to resort to tiptoeing around the
compatibility flag.

Differential Revision: https://reviews.llvm.org/D76510