Added citation file

CITATION.cff

@@ -0,0 +1,24 @@
+cff-version: 1.1.0
+message: "If you use iflye in your research, please cite it using these metadata."
+abstract: iflye is a framework to implement and evaluate algorithms for virtual network embedding.
+authors:
+  - family-names: Kratz
+    given-names: Maximilian
+title: incremental fast leightweight (y) virtual network embedding
+version: 0.0.1
+date-released: 2021-07-29
+url: "https://github.com/maxkratz/iflye"
+keywords:
+  - virtual network embedding
+  - vne
+  - data center
+  - network
+  - model-driven software engineering
+  - simulation
+  - eclipse modeling framework
+  - pattern-matching
+  - model
+  - integer linear programming
+  - emoflon
+  - graph transformation
+license: "GPL-3.0"

README.md

@@ -5,7 +5,7 @@
 
 ## Installation (development)
 
-* Install [AdoptOpenJDK 13 (HotSpot JVM)](https://adoptopenjdk.net/releases.html?variant=openjdk13&jvmVariant=hotspot).
+* Install [AdoptOpenJDK 13 (HotSpot JVM)](https://adoptopenjdk.net/releases.html?variant=openjdk13&jvmVariant=hotspot) or newer.
 * Install eMoflon::IBeX as described [here](https://github.com/eMoflon/emoflon-ibex#how-to-develop).
 * Install [Gurobi](https://www.gurobi.com/) in version `8.1.1` and activate a license for your computer.
 * Launch a runtime workspace (while using a runtime Eclipse) as stated in the eMoflon::IBeX installation steps.