Provide a testsuite for EDN format

[ligurio]

The repository contains a plain-english description of EDN format.
However different implementations can be incomplete or contain bugs. This can be lead to interoperability problems.
It would be nice to have a testsuite that will check EDF format producers and consumers for conformance to EDN format specification.

Tests for certain implementations:

• https://github.com/swaroopch/edn_format/blob/master/tests.py
• https://github.com/edn-format/data.edn/tree/master/test/org/edn_format/data
• https://github.com/edn-format/edn-dot-net/tree/master/TestData