[analyzer] SATest: Add initial docker infrastructure

Summary:
Static analysis is very sensitive to environment.
OS and libraries installed can affect the results.  This fact makes
it extremely hard to have a regression testing system that will
produce stable results.

For this very reason, this commit introduces a new dockerized testing
environment, so that every analyzer developer can check their changes
against previous analysis results.

Differential Revision: https://reviews.llvm.org/D81571