ipatests: test_trust: Add test to cover lookup of trusdomains

Adds an integration tests that checks that all trustdomains are
able to be found by trustdomain-find command right after the
trust has been established.

Also moves some code to allow easier adding common test cases for
both POSIX and non-POSIX test classes.

https://fedorahosted.org/freeipa/ticket/4208

Reviewed-By: Petr Viktorin <pviktori@redhat.com>
Fix parsing of long nicknames in certutil -L output.

https://fedorahosted.org/freeipa/ticket/4453

Reviewed-By: Petr Viktorin <pviktori@redhat.com>
Allow to add host if AAAA record exists

http://fedorahosted.org/freeipa/ticket/4164

Reviewed-By: Petr Viktorin <pviktori@redhat.com>
Tests: host tests with dns

Test for: https://fedorahosted.org/freeipa/ticket/4164

Reviewed-By: Petr Viktorin <pviktori@redhat.com>
Convert external CA chain to PKCS#7 before passing it to pkispawn.

https://fedorahosted.org/freeipa/ticket/4397