added ability to change password

public/js/skin3d.js

@@ -38,10 +38,34 @@ const uploadCape = async (event) => {
        window.location = window.location.href+'?eraseCache=true';
 }
 
+const changePassword = async (event) => {
+	event.preventDefault();
+
+	const oldPassword = document.getElementById("oldPassword").value
+	const newPassword = document.getElementById("newPassword").value
+
+	if (oldPassword == newPassword) {
+		alert("You cannod change your password to the same!")
+		return;
+	}
+
+	await fetch(`/api/changePassword`, {
+		method: "POST",
+		headers: {
+			"Content-Type": "application/json"
+		},
+		body: JSON.stringify({
+			oldPassword,
+			newPassword
+		})
+	});
+	alert("Password has been changed!");
+}
+
 
 window.onload = async function() {
 	document.getElementById("skinForm").addEventListener("submit", uploadSkin)
-
+	document.getElementById("passwordChangeForm").addEventListener("submit", changePassword);
 	if (document.getElementById("cape")) {
     	document.getElementById("cape").addEventListener("click", () => { set_cape_type("cape") }, false);
     	document.getElementById("cape").checked = true;