[TASK] Improve .htaccess files

Improve the example .htaccess file by adding rules for caching,
MIME types and CORS. Also, the rewrite rules are extended to block
access to certain files and folders.

Additionally all rules are made compatible for Apache 2.4 as well.

Resolves: #23078
Resolves: #66235
Releases: master, 6.2
Change-Id: I629f524b5a209769601f04a74bb7434736058ab8
Reviewed-on: http://review.typo3.org/39254


Reviewed-by: Stephan Großberndt <stephan@grossberndt.de>
Tested-by: Stephan Großberndt <stephan@grossberndt.de>
Reviewed-by: Markus Klein <markus.klein@typo3.org>
Tested-by: Markus Klein <markus.klein@typo3.org>