Clarify that all functions are exported
Mention is_unroutable_ipv4 in Changes
Add back is_innet_ipv4 tests
Test that all is_$type_ipv4 subs return false on bad ips

Fix bad var names and add strict & warnings
Add unroutable to spelling whitelist and sort words
Add a .gitignore file
Add is_X_ipv6 subs and test them