[FEATURE] create extension upload folder

Relates: #45704
Merge pull request #14 from jaguerra/master

[FEATURE] create extension upload folders
[BUGFIX] Concatenate arrays instead of merging
[TASK] Add cruser_id to new sysnews

If a news is created, the field cruser_id should be filled with the
uid of the cli user.
[FEATURE] Runs tcemain commands with a faked admin backend user
[TASK] Add total count of extensions
[BUGFIX] Add missing class to ext_autoload
[FEATURE] Add count of local installed exts
[TASK] Add a .gitignore file.
[TASK] Add version restrictions to ext_emconf.php.
Merge pull request #17 from oliverklee/master

[TASK] Add a .gitignore file and version restrictions in ext_emconf
Merge pull request #15 from lars85/master

[BUGFIX] Concatenate arrays instead of merging
Merge pull request #16 from georgringer/master

If a news is created, the field cruser_id should be filled with the uid of the cli user.
Merge branch 'master' into madsbrunn/master

Conflicts:
	Classes/Cli/Dispatcher.php
	Classes/Service/ExtensionApiService.php
[FIX] fix createUploadfolders command in Dispatcher
[TASK] cleanup Dispatcher (whitespaces mostly)
[TASK] Dispatcher code cleanup
[TASK] code cleanup
[TASK] cleanup and refactor ExtensionApiService
[TASK] cleanup and refactor ExtensionApiService