Minimum stability stable.
Add php artisan clear-compiled to post-install-cmd, as proposed in
laravel/framework#3152

Signed-off-by: crynobone <crynobone@gmail.com>
Merge pull request #2560 from crynobone/feature/post-install-cmd

Add php artisan clear-compiled to post-install-cmd
Remove makeshift upgrade guide. Docs should be used.
Merge branch 'master' into develop