tests: Add tests for machine keytab auth

.travis.yml

@@ -1,8 +1,6 @@
 sudo: required
 language: python
-dist:
-  - trusty
-  - xenial
+dist: trusty
 python:
   - "2.7"
 after_success:
@@ -10,18 +8,12 @@ after_success:
 virtualenv:
   system_site_packages: true
 install:
-  - echo "127.0.0.1 localhost" | sudo tee /etc/hosts
-  - echo "127.0.1.1 ca.example.lan ca" | sudo tee -a /etc/hosts
-  - echo "127.0.0.1 vpn.example.lan vpn" | sudo tee -a /etc/hosts
-  - echo "127.0.0.1 www.example.lan www" | sudo tee -a /etc/hosts
-  - sudo mkdir -p /etc/systemd/system
+  - sudo mkdir -p /etc/systemd/system # Until Travis is stuck with 14.04
   - sudo pip install -r requirements.txt
   - sudo pip install codecov pytest-cov requests-kerberos
   - sudo pip install -e .
 script:
   - sudo find /home/ -type d -exec chmod 755 {} \; # Allow certidude serve to read templates
-  - sudo useradd adminbot -G sudo -p '$1$PBkf5waA$n9EV6WJ7PS6lyGWkgeTPf1'
-  - sudo useradd userbot -G users -p '$1$PBkf5waA$n9EV6WJ7PS6lyGWkgeTPf1' -c "User Bot,,,"
   - sudo chmod 777 . # Allow forked processes to write .coverage files
   - sudo coverage run --parallel-mode --source certidude -m py.test tests
   - sudo coverage combine