BAMPFA-79: Initial commit of structured date parser.
BAMPFA-79: Change a comment, and uncomment all displayDate alternatives.
BAMPFA-79: Add antlr error listener. Refactor date qualifiers.
BAMPFA-79: Add tests.
BAMPFA-79: Add circa calculation.
BAMPFA-79: Reorganize test cases.
BAMPFA-79: Add todos to grammar.
BAMPFA-79: Add structureddate module to parent pom.
BAMPFA-79: Fix circa calculation for dates in the future.
BAMPFA-79: Default scalarValuesComputed to true.
BAMPFA-79: Improve error handling.
BAMPFA-79: Lowercase all tokens, and allow 'ce' for ad.
BAMPFA-79: Allow dot after short months, and ca for circa.
BAMPFA-79: Handle month year and year month.
BAMPFA-79: Allow MM-DD-YYYY.
BAMPFA-79: Allow single date with era.
BAMPFA-79: Some grammar reorganization.
BAMPFA-79: More grammar reorganization.
BAMPFA-79: Handle year ranges.
BAMPFA-79: More grammar cleanup, and add support for date ranges.