v1.5.5

Features:

• Disco now disambiguates conformance choices and removes mandatory fallbacks by default
• Text inside monospace is no longer checked for missing spaces after periods

Fixes:

• Better handling of the formatting of zap_cluster_list.json
• Normalize cross-references before eliminating link stutter, to avoid re-adding stutter
• Allow some escapes in conformance to get around special asciidoc substitutions