Fixed ansible distribution check template error

This fixes both:
- [inkatze#42](inkatze#43): using ansible_distribution_major_version instead of ansible_distribution_version
- [inkatze#62](inkatze#62): using is version instead of version_compare

tasks/configure.yml

@@ -78,7 +78,7 @@
       permanent: yes
       immediate: yes
       state: enabled
-  when: ansible_distribution_version|version_compare(7, '=') and wildfly_manage_firewall
+  when: ansible_distribution_major_version is version('7', '=') and wildfly_manage_firewall
 
 - meta: flush_handlers