Log Message:
Update to 1.25
Update BUILD_DEPENDS

Upstream changes:
Changes for version 1.25 - 2018-05-11
Applied several pull requests by tinita
Support trailing comments (PR #189, PR #190, PR #191)
Remove unused code (PR #192)
Use Test::Deep to actually test correctly for class names (PR #193)
Fix loading of mapping key which starts with `= ` (PR #194)
Fix loading strings with multiple spaces (PR #172)
Allow more characters in anchor name (PR #196)
Add $YAML::LoadBlessed for disabling loading objects (PR #197)
Applied several pull requests by tinita
Disable test with long string under certain conditions (PR #201)
Quote scalar if it equals '=' (PR #202)
Multiple regexp roundtrip does not grow (PR #203)
Add support for compact nested block sequences (PR #204)
Support reverse order of block scalar indicators (PR #205)
Support nested mappings in sequences (PR #206)