Make version check work on the lowest common version denominator

Add notice about Travis Checks

Maybe it helps in the future so we won't forget it again 

Revert "Updating license headers"

apply suggestions from @atmoz to fix SFTP setup

Fix warning in filecache gc

Add default value for remote_id

Fix file move/copy when storage space is not enough

clarify link on apps management to the dev documentation

Move UTF-8 check to setup

Fixes WebDAV copy

Append search results to custom container

Add async command system to handle asynchronous operations

Remove dependency from arbitrary data object structure for easier usage

Remove uneeded assignment

Fixes SQLite migration with non-null column.

This reverts commit 6a1a4880.

Failing mysql master tests

Clean up AppFramework database layer

using Doctrine\DBAL\Connection::executeUpdate()