Issue #2982680 by greg.1.anderson, mbaynton, Mixologic, jibran, webflo, Mile23, phenaproxima, AaronMcHale, Charlie ChX Negyesi, nicksanta: Add composer-ready project templates to Drupal core

Issue #3018673 by nicksanta, dhirendra.mishra, jibran: Add support for RFC5785 change password well known resource

Issue #2191107 by jessebeach, longwave, nicksanta, jhodgdon, xjm: Update API documentation for _theme() to clearly indicate that it is for internal use only.