don't hide the exception

Author: hauner

src/main/java/io/openapiprocessor/maven/ProcessMojo.java

@@ -64,7 +64,7 @@ public void execute () throws MojoExecutionException, MojoFailureException {
             }
 
         } catch (Exception e) {
-            throw new MojoExecutionException ("openapi-processor-" + id + " execution failed!");
+            throw new MojoExecutionException ("openapi-processor-" + id + " execution failed!", e);
         }
     }