5.1.3: Allow ::class on objects

• Allowed ::class on objects (PHP 8.0 forward compatibility) - @thekid

5.1.2: Promotion of by-reference parameters fix

• Fixed promotion for by-reference arguments - @thekid

5.1.1: Operator precedence fix

• Fixed ternary and instanceof operators' precedence - @thekid

5.1.0: PHP 8 syntax adoptions

• Merged PR #82: Allow chaining scope resolution operator :: - @thekid
• Merged PR #81: Allow instanceof (<expr>) as syntax - @thekid
• Merged PR #80: Allow new (<expr>) as syntax - @thekid

5.0.0: Drop PHP5

• Merged PR #70: Extract compact methods; to use these, require the
  library https://github.com/xp-lang/php-compact-methods
  (@thekid)
• Merged PR #79: Convert testsuite to baseless tests - @thekid
• Merged PR #78: Deprecate curly brace syntax for offsets; consistent
  with PHP 7.4
  (@thekid)
• Added support for XP 10 and newer versions of library dependencies
  (@thekid)
• Implemented xp-framework/rfc#334: Drop PHP 5.6. The minimum required
  PHP version is now 7.0.0!
  (@thekid)

4.3.1: XP10 compatiblity

• Added compatibility with XP 10, see xp-framework/rfc#333 - @thekid

4.3.0: Hashtag comments

• Fixed global constants in ternaries being ambiguous with goto labels
  (@thekid)
• Fixed emitting switch statements and case labels' ambiguity w/ goto
  (@thekid)
• Fixed an operator precedence problem causing incorrect nesting in the
  parsed AST for unary prefix operators.
  (@thekid)
• Merged PR #77: Add support for #-style comments including support for
  XP style annotations
  (@thekid)

4.2.1: Abstract and final types fix

• Fixed parser to allow "extending" final and abstract types - @thekid

4.2.0: Ast subcommand

• Fixed issue #74: No longer shadow compiler errors in certain cases
  (@thekid)
• Merged PR #75: Add "ast" subcommand to display the abstract syntax tree
  (@thekid)

4.1.0: Annotations in anonymous classes

• Merged PR #73: Add support for annotations in anonymous classes
  (@thekid)