Till now the per-line glitches counters were only enabled with the
confusingly named DEBUG_GLITCHES (which would not turn glitches off
when disabled). Let's instead change it to DEBUG_COUNTERS and make sure
it's enabled by default (though it can still be disabled with
-DDEBUG_GLITCHES=0 just like for DEBUG_STRICT). It will later be
expanded to cover more counters.
61d633a3ac
