Pessoal, estou usando o Gnome na versão 16.04. Quando dou o comando "composer global require "laravel/installer=~1.1", ele dá o seguinte erro "Changed current directory to /home/vitorergang/.composer Cannot create cache directory /home/vitorergang/.composer/cache/repo/https---repo.packagist.org/, or directory is not writable. Proceeding without cache Cannot create cache directory /home/vitorergang/.composer/cache/files/, or directory is not writable. Proceeding without cache ./composer.json is not writable."