Merge pull request #218 from ebiggers/cli-tests

Merge pull request #218 from ebiggers/cli-tests

Add tests for command-line interface

Add tests that directly test the fscrypt command-line tool.

See cli-tests/README.md for information about the test framework.

The following test scripts are included:

* t_change_passphrase
* t_encrypt_custom
* t_encrypt_login
* t_encrypt_raw_key
* t_encrypt
* t_lock
* t_not_enabled
* t_not_supported
* t_passphrase_hashing
* t_setup
* t_status
* t_unlock
* t_v1_policy_fs_keyring
* t_v1_policy

Unfortunately, we can't actually make Travis CI run these tests yet because they need kernel v5.4 or later, and Travis CI doesn't support an Ubuntu version that has that yet. But for now, they can be run manually using make cli-test.