Merge branch 'master' into auth_source_factories

.travis.yml

CONTRIBUTING.md

composer.json

composer.lock

config-templates/authmemcookie.php

config-templates/authsources.php

config-templates/config.php

docs/simplesamlphp-authproc.md

docs/simplesamlphp-changelog.md

docs/simplesamlphp-customauth.md

docs/simplesamlphp-ecp-idp.md

docs/simplesamlphp-install.md

docs/simplesamlphp-metadata-extensions-ui.md

docs/simplesamlphp-reference-idp-remote.md

docs/simplesamlphp-theming.md

docs/simplesamlphp-upgrade-notes-1.15.md

lib/SimpleSAML/Auth/LDAP.php

lib/SimpleSAML/Auth/TimeLimitedToken.php

lib/SimpleSAML/AuthMemCookie.php

lib/SimpleSAML/Configuration.php