Add Readmes for subprojects

dmnverifierapi/README.md

+# Master Thesis - Implementation Project - Backend
+
+[Thesis Project](https://gitlab.uni-koblenz.de/jonasblatt/ma-jonasblatt-thesis) of Jonas Blatt in WiSe 19/20 - SoSe20
+
+This project contains all source files of the implementation, created for the master thesis.
+
+- [Frontend Project](../dmnverifierfrontend)
+
+## Backend
+Based on
+- [Quarkus](https://quarkus.io/guides/maven-tooling)
+- [Camunda DMN](https://github.com/bpmn-io/dmn-js)

dmnverifierfrontend/README.md

+# Master Thesis - Implementation Project - Backend
+
+[Thesis Project](https://gitlab.uni-koblenz.de/jonasblatt/ma-jonasblatt-thesis) of Jonas Blatt in WiSe 19/20 - SoSe20
+
+This project contains all source files of the implementation, created for the master thesis.
+
+- [Backend Project](../dmnverifierapi)
+
+## Frontend
+TODO..