[TASK] TemplateService: Add verbose option

The TemplateService class contains the functionality
to parse the TypoScript constants that haven't
been replaced yet.

This is done each time in the frontend, although
it is only useful when $this->tt_track is active,
thus when a BE user is logged in, who can read the info.

The improvement in this patch is to skip the strstr()
check if not set, thus making first-hit page calls a bit
quicker and the code more readable.

Releases: 6.3
Resolves: #61512
Change-Id: I8ebdb5e4bdc643e24dc9328ef48ed91a67376636
Reviewed-on: http://review.typo3.org/32706
Reviewed-by: Tymoteusz Motylewski <t.motylewski@gmail.com>
Tested-by: Tymoteusz Motylewski <t.motylewski@gmail.com>
Reviewed-by: Anja Leichsenring <aleichsenring@ab-softlab.de>
Tested-by: Anja Leichsenring <aleichsenring@ab-softlab.de>