Test Perl 5.8 on travis

5.8.8 is shipped with RHEL 5, also oldest version supported by Travis

Author: df7cb

.travis.yml

@@ -16,7 +16,7 @@ dist: trusty
 sudo: required
 language: perl
 perl:
-  - '5.10'
+  - '5.8' # 5.8.8 is shipped with RHEL 5, also oldest version supported by Travis
   - '5.24'
 
 before_install: