added hasGroupSupport to Permission class

src/net/milkbowl/vault/permission/Permission.java

@@ -649,4 +649,10 @@ public abstract class Permission {
      * @return an Array of String of all groups
      */
     abstract public String[] getGroups();
+    
+    /**
+     * Returns true if the given implementation supports groups.
+     * @return true if the implementation supports groups
+     */
+    abstract public boolean hasGroupSupport();
 }

src/net/milkbowl/vault/permission/plugins/Permission_DroxPerms.java

@@ -137,4 +137,9 @@ public class Permission_DroxPerms extends Permission {
         return API.getGroupNames();
     }
 
+    @Override
+    public boolean hasGroupSupport() {
+        return false;
+    }
+
 }

src/net/milkbowl/vault/permission/plugins/Permission_GroupManager.java

@@ -396,4 +396,9 @@ public class Permission_GroupManager extends Permission {
     public boolean hasSuperPermsCompat() {
         return true;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_Permissions3.java

@@ -298,4 +298,9 @@ public class Permission_Permissions3 extends Permission {
     public boolean hasSuperPermsCompat() {
         return false;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_PermissionsBukkit.java

@@ -232,4 +232,9 @@ public class Permission_PermissionsBukkit extends Permission {
     public boolean hasSuperPermsCompat() {
         return true;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_PermissionsEx.java

@@ -282,4 +282,9 @@ public class Permission_PermissionsEx extends Permission {
     public boolean hasSuperPermsCompat() {
         return true;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_Privileges.java

@@ -159,4 +159,9 @@ public class Permission_Privileges extends Permission {
     public boolean hasSuperPermsCompat() {
         return true;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_SimplyPerms.java

@@ -219,4 +219,9 @@ public class Permission_SimplyPerms extends Permission{
         return perms.getAllGroups().toArray(new String[0]);
     }
 
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
+
 }

src/net/milkbowl/vault/permission/plugins/Permission_Starburst.java

@@ -299,4 +299,9 @@ public class Permission_Starburst extends Permission {
             return false;
         }
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_SuperPerms.java

@@ -105,4 +105,9 @@ public class Permission_SuperPerms extends Permission {
 	public boolean hasSuperPermsCompat() {
 		return true;
 	}
+
+    @Override
+    public boolean hasGroupSupport() {
+        return false;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_Xperms.java

@@ -177,4 +177,9 @@ public class Permission_Xperms extends Permission {
     public String[] getGroups() {
         return perms.getXperms().getGroups();
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_bPermissions.java

@@ -273,4 +273,9 @@ public class Permission_bPermissions extends Permission {
     public boolean hasSuperPermsCompat() {
         return true;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_bPermissions2.java

@@ -197,4 +197,9 @@ public class Permission_bPermissions2 extends Permission {
     public boolean hasSuperPermsCompat() {
         return true;
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }

src/net/milkbowl/vault/permission/plugins/Permission_zPermissions.java

@@ -206,4 +206,9 @@ public class Permission_zPermissions extends Permission {
     public String[] getGroups() {
         return service.getAllGroups().toArray(new String[0]);
     }
+
+    @Override
+    public boolean hasGroupSupport() {
+        return true;
+    }
 }