[!!!][TASK] Remove devlog constants

Drop three error related constants from bootstrap:
TYPO3_DLOG, TYPO3_ERROR_DLOG, TYPO3_EXCEPTION_DLOG

Removal of these constants has been prepared in v8
and can be done now. This unblocks further logging
related works.

Along the way, the two TYPO3_CONF_VARS "enable_errorDLOG"
and "enable_exceptionDLOG" can be dropped.

The extension scanner can find usages of these constants,
making the patch not less breaking, but usage detection
within extensions is safe and thus helps a lot to spot them.

A new matcher is added to the extension scanner to
scan for usages of global constants.

Resolves: #82162
Releases: master
Change-Id: I6310866738e5cda79a807239846f64996ec76974
Reviewed-on: https://review.typo3.org/53212


Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>