Better api generation

Things to consider:

• breaking changes (removed imports), so up minor version, because we are still not in 1.0

src/main/jastadd/backend/API.jadd

@@ -15,11 +15,15 @@ aspect BackendAPI {
   public void RelationComponent.generateAPI(StringBuilder sb) {
     if (otherSide().isNavigable()) {
       if (multiplicityOne() || multiplicityOpt()) {
+        generateGetOne(sb);
         if (otherSide().multiplicityOne() || otherSide().multiplicityOpt()) {
           generateBiOneOne(sb);
         } else if (otherSide().multiplicityMany()) {
           generateBiOneMany(sb);
         }
+        if (isOpt()) {
+          generateExtraOptAPI(sb);
+        }
       } else if (multiplicityMany()) {
         if (otherSide().multiplicityOne() || otherSide().multiplicityOpt()) {
           generateBiManyOne(sb);
@@ -29,13 +33,38 @@ aspect BackendAPI {
       }
     } else {
       if (multiplicityOne() || multiplicityOpt()) {
+        generateGetOne(sb);
         generateDirectedZeroOneAPI(sb);
+        if (isOpt()) {
+          generateExtraOptAPI(sb);
+        }
       } else if (multiplicityMany()) {
         generateDirectedManyAPI(sb);
       }
     }
   }
 
+  public void RelationComponent.generateGetOne(StringBuilder sb) {
+    sb.append(ind(1) + "public " + ofTypeDecl() + " " + getTypeUse().decl() + ".");
+    if (useJastAddNames) {
+      sb.append("get" + nameCapitalized());
+    } else {
+      sb.append(name());
+    }
+    sb.append("() {\n");
+    if (resolverHelper | serializer) {
+      sb.append(ind(2) + "if (" + getImplAttributeField() + " != null && " + getImplAttributeField() + ".is$Unresolved()) {\n");
+        sb.append(ind(3) + "if (" + getImplAttributeField() + ".as$Unresolved().getUnresolved$ResolveOpposite()) {\n");
+          sb.append(ind(4) + "set" + nameCapitalized() + "(resolve" + nameCapitalized() + "ByToken(" + getImplAttributeField() + ".as$Unresolved().getUnresolved$Token()));\n");
+        sb.append(ind(3) + "} else {\n");
+          sb.append(ind(4) + "set" + getImplAttributeName() + "(resolve" + nameCapitalized() + "ByToken(" + getImplAttributeField() + ".as$Unresolved().getUnresolved$Token()));\n");
+        sb.append(ind(3) + "}\n");
+      sb.append(ind(2) + "}\n");
+    }
+    sb.append(ind(2) + "return get" + getImplAttributeName() + "();\n");
+    sb.append(ind(1) + "}\n");
+  }
+
   public void RelationComponent.generateExtraOptAPI(StringBuilder sb) {
     // has
     sb.append(ind(1) + "public boolean " + getTypeUse().decl());