Support for *-block and *-inline properties #174

Currently, the ExCSS parser strips all *-block and *-inline properties e.g. padding-inline

Steps to reproduce:

1. Parse the following string: ".appbar { padding-block: 1px; padding-inline: 1px; }"
2. Inspect the Style text

Expected: The text should be padding-block: 1px; padding-inline: 1px;
Actual: The text is empty