v0.3.0

• Added PropertyCheck::edgeCases() and PROPERTY_EDGE_CASES (mixin or
  none), reaching core 0.3's switch for the numeric boundary bias. Turning it
  off stops a property that cannot use 0, ±1 or a range's ends from
  spending one run in five on a value it discards. The variable overrides the
  chain, like every other CI-facing knob, and an unknown value throws rather
  than silently keeping the bias it was told to drop.
• Requires rasuvaeff/property-testing-core ^0.3.