chore: update verifier options

BREAKING CHANGE: There are several changes to the `VerifierOptions`. To migrate:

  * Replace `verbose` with `logLevel: "DEBUG"` (logLevels of `DEBUG` and below now imply `verbose` where appropriate)
  * Replace `consumerVersionTag` with the `consumerVersionTags` array
  * Replace `providerVersionTag` with the `providerVersionTags` array
  * Replace `tags` with `consumerVersionTags` or `providerVersionTags` as appropriate.
* Some `VerifierOptions` have been removed entirely:
  * `customProviderHeaders` has been removed. If you need this functionality, set an
    appropriate request filter with the `requestFilters` option instead.
  * All logging and reporting is now on standard out (this was the default before).
    This means `logDir` / `format` / `out` have all been removed. If your ecosystem needs
    the ability to customise logging and reporting, please let us know by opening an issue.
  * The undocumented option `monkeypatch` has been removed. The use cases for this
    feature are mostly covered by other options.

MIGRATION.md

@@ -0,0 +1,24 @@
+# Pact-js migration guide
+
+This guide is for migrating to a new version of pact-js.
+
+# v10.x.x from v9.x.x
+
+## Verifier Options
+
+There are several changes to the `VerifierOptions`. To migrate:
+
+- Replace `verbose` with `logLevel: "DEBUG"` (logLevels of `DEBUG` and below now imply `verbose` where appropriate)
+- Replace `consumerVersionTag` with the `consumerVersionTags` array
+- Replace `providerVersionTag` with the `providerVersionTags` array
+- Replace `tags` with `consumerVersionTags` or `providerVersionTags` as appropriate.
+
+Some options have been removed entirely:
+
+- `customProviderHeaders` has been removed. If you need this functionality, set an
+  appropriate request filter with the `requestFilters` option instead.
+- All logging and reporting is now on standard out (this was the default before).
+  This means `logDir` / `format` / `out` have all been removed. If your ecosystem needs
+  the ability to customise logging and reporting, please let us know by opening an issue.
+- The undocumented option `monkeypatch` has been removed. The use cases for this
+  feature are mostly covered by other options.