v0.9.0

Breaking changes:

• framework API (general):
  • Defined a new *ElseNull() method naming convention, to use instead of
    *OrNull*(), clarifying the contexts in which each is appropriate.
  • Reworked method naming convention for type/value-checking methods to be
    mustBe*(), instead of using either expect*() or check*().
  • As a result of the above, renamed a bunch of methods throughout the system.

Other notable changes:

• net-util:
  • Now recognize EC PRIVATE KEY as a label in PEM files for private keys.
• webapp-builtins:
  • StaticFiles: Added indexFile configuration option.
• webapp-util:
  • New class StaticFileResponder, extracted from
    webapp-builtins.StaticFiles.