• features:
• add compare for version comparison / sorting (with npm-compatible prerelease ordering)
• add max-satisfying for resolving the latest version in a list satisfying a range
• add valid / valid-range for syntax check
• bug fix:
• fix fit: a version with a larger higher-significance component but smaller
  lower component was wrongly rejected (e.g. fit(\"1.5.0\", \"^1.3.2\") returned false)
• fix fit: prerelease versions no longer satisfy release-only ranges;
  caret now locks the left-most non-zero component (npm semantics)
• fix parse: build metadata (1.2.3+build.1) is now captured separately instead of
  corrupting the patch component; it never affects precedence (semver spec)
• tweaks:
• add build / test npm scripts; rewrite test with assertions

• fix bug: prevent error when parsing undefined

• add main and browser field in package.json.
• upgrade modules
• release with compact directory structure

init commit