Runners now use the runnergroup class instead of strings

ref #1

src/models/Runner.ts

@@ -1,12 +1,14 @@
 import {
     IsInt,
+    IsObject,
     IsString
 } from "class-validator";
+import { RunnerGroup } from './RunnerGroup';
 
 /**
  * Defines the contract runner class (from which the runner sponsoring contracts get generated).
 */
-export class ContractRunner {
+export class Runner {
     /**
      * The runner's id.
      */
@@ -34,6 +36,6 @@ export class ContractRunner {
     /**
      * The runner's group.
      */
-    @IsString()
-    group: string;
+    @IsObject()
+    group: RunnerGroup;
 }

src/models/RunnerCard.ts

@@ -5,7 +5,7 @@ import {
     IsObject,
     IsString
 } from "class-validator";
-import { ContractRunner } from './ContractRunner';
+import { Runner } from './Runner';
 
 /**
  * Defines the runner card class (used to create runner card pdfs).
@@ -21,7 +21,7 @@ export class RunnerCard {
      * The card's associated runner.
      */
     @IsObject()
-    runner: ContractRunner | null;
+    runner: Runner | null;
 
     /**
      * The card's code.