Remove requirement on globally configured git name and email

Setting the name and email in `~/.password-store/.git/config` is insufficient for Ripasso. Ripasso requires these configurations to be set globally, which seems unnecessary, as repository-specific settings should suffice. ## Current behaviour: Ripasso won't start. Error message: ``` You haven't configured you name and email in git, doing so will make cooperation with your team easier, you can do it like this: git config --global user.name "John Doe" git config --global user.email "email@example.com" ``` ...(etc). ## Desired behaviour: Start ripasso, and use the configuration in the `~/.password-store` git repository.