mmark-ext-0.0.1.2: CHANGELOG.md

## MMark Ext 0.0.1.2

* Compiles with `modern-uri-0.2.0.0` and later.

## MMark Ext 0.0.1.1

* Fixed test suite failure with newer MMark versions. This version is to be
  used with `mmark-0.0.2.0` and later.

## MMark Ext 0.0.1.0

* Initial release.