[TASK] Improve error output in TS if INCLUDE_TYPOSCRIPT file not found

The TSOB should show if a file which should be included could not be found.

Due the fact that parts of the TypoScript parser are written with static
methods, the only way is to check the TypoScript lines for the string
"### ERROR".

Resolves: #17090
Releases: master, 6.2
Change-Id: I6679413e9ff7ca027e23e9b2d6927fd95f8f4595
Reviewed-on: http://review.typo3.org/35516
Reviewed-by: Markus Klein <klein.t3@reelworx.at>
Tested-by: Markus Klein <klein.t3@reelworx.at>