Replace the single user (defined in /data/config.php) with a multi user management thing

public/viewjs/userform.js

@@ -0,0 +1,73 @@
+$('#save-user-button').on('click', function(e)
+{
+	e.preventDefault();
+
+	if (Grocy.EditMode === 'create')
+	{
+		Grocy.Api.Post('users/create', $('#user-form').serializeJSON(),
+			function(result)
+			{
+				window.location.href = U('/users');
+			},
+			function(xhr)
+			{
+				console.error(xhr);
+			}
+		);
+	}
+	else
+	{
+		Grocy.Api.Post('users/edit/' + Grocy.EditObjectId, $('#user-form').serializeJSON(),
+			function(result)
+			{
+				window.location.href = U('/users');
+			},
+			function(xhr)
+			{
+				console.error(xhr);
+			}
+		);
+	}
+});
+
+$('#user-form input').keyup(function (event)
+{
+	var element = document.getElementById("password_confirm");
+	if ($("#password").val() !== $("#password_confirm").val())
+	{
+		element.setCustomValidity("error");
+	}
+	else
+	{
+		element.setCustomValidity("");
+	}
+
+	Grocy.FrontendHelpers.ValidateForm('user-form');
+});
+
+$('#user-form input').keydown(function (event)
+{
+	if (event.keyCode === 13) //Enter
+	{
+		if (document.getElementById('user-form').checkValidity() === false) //There is at least one validation error
+		{
+			event.preventDefault();
+			return false;
+		}
+		else
+		{
+			$('#save-user-button').click();
+		}
+	}
+});
+
+if (GetUriParam("changepw") === "true")
+{
+	$('#password').focus();
+}
+else
+{
+	$('#username').focus();
+}
+
+Grocy.FrontendHelpers.ValidateForm('user-form');