disable the app code checker - some previous shipped apps cannot be installed from the appstore now :facepunch:

During performance optimization I have discovered that the installer scans all files for the blacklisted words. This greatly impacts speed on lower end devices such as the raspberry pie. This commit limits it to PHP files which seems to achieve the desired effect. 

I have used the --include option to achieve this, see http://stackoverflow.com/questions/1987926/how-do-i-grep-recursively

This contribution is MIT licensed

filter installed and not-installed apps properly

kill unneeded file

load category 'Installed' on page load

adding documentation links

new apps mgmt: first style adjustment

apps mgmt: only show license and preview if they exist

adding buttons

new apps mgmt: fix for mobile

use app icon if available

new apps mgmt: position enable/disable toggle to the right

new apps mgmt: proper display of icons or previews

new apps mgmt: fix loading spinner

reenable group selection for apps

new apps mgmt: position enable button normally again

new apps mgmt: clarify wording from 'Installed' to 'Enabled'

reintroduce enable/disable

Move rating image path generation to client-side

Move expression outside of l10n

fix group handling

add buttons for 'More apps' and 'Add your app' again

disable changed date of app for now

adding recommended label

style 'Recommended' app tag

fixing php warning

sort by rating

adding meta-category 'Recommended'

 Only show existing documentation links

lacy loading of screenshots

making group based app activation work again

adding support to get the app icon not only by the app name but also simply by the fixed name 'app.svg'

adding app.svg for all core apps

query string '?installed' is not longer needed

update and uninstall is back + error feedback

remove unneeded parameter

fix alignment of 'recommended' label

in order to prevent false-positives on the code checker - exec and eval will not longer be grepped for

append file extension to the temporary file which contains the downloaded archive - in case of zip files fileinfo doesn't seem to return anything reliable

those apps will have to use the public api

Apps can now specify a minimum and maximum version of ownCloud in which
they are supported.

* test case added to avoid adding them later

This patch was automatically generated as part of the following inspection:
https://scrutinizer-ci.com/g/owncloud/core/inspections/cdfecc4e-a37e-4233-8025-f0d7252a8720

Enabled analysis tools:
 - PHP Analyzer
 - JSHint
 - PHP Copy/Paste Detector
 - PHP PDepend

Issue #7111

switch code checker on by default. apps are not allowed to access some of the internal classes where we have a public api for now

See #4716

See #5202

Conflicts:
	lib/private/vcategories.php