We have some really old code (Makefile days) for checking if syntax

highlighting can be enabled, based on having Pygments, and having a

minimum version of it. This code, in combination with some other code,

ends up creating some ugly and unnecessary circular dependencies between

parts of the product that only appear if you start importing certain

modules first.
These days, we have actual dependencies that get installed with the

product. This check is no longer useful, and causes more harm than good.

This change removes the check and all calls.

Unit tests pass.
Syntax highlighting still works.
Tested the circular dependency issue I hit in an extension, and the

problem went away.