Bypass EULA on DMG file when installing

I've added a new provider `appdmg_eula_charles` to the module, and switched the package provider for Charles to use this. This avoids needing to accept the EULA when mounting the DMG, which is impossible to do if installing with Puppet, and correctly installs Charles.app.

I've named it `appdmg_eula_charles` so that it doesn't conflict with the `appdmg_eula` provider I'll submit to the boxen module. This means users won't be required to upgrade their version of the boxen module to install Charles.