Make MatrixHttpApi a generic API interface; move specifics to MatrixClient.

Add a utils file to store common operations like map() and encodeParams().
Modify MatrixClient and MatrixHttpApi to accepts opts as constructors.

lib/utils.js

@@ -0,0 +1,52 @@
+"use strict";
+
+
+// avoiding deps on jquery and co
+module.exports.encodeParams = function(params) {
+    var qs = "";
+    for (var key in params) {
+        if (!params.hasOwnProperty(key)) { continue; }
+        qs += "&" + encodeURIComponent(key) + "=" +
+                encodeURIComponent(params[key]);
+    }
+    return qs.substring(1);
+};
+
+module.exports.encodeUri = function(pathTemplate, variables) {
+    for (var key in variables) {
+        if (!variables.hasOwnProperty(key)) { continue; }
+        pathTemplate = pathTemplate.replace(
+            key, encodeURIComponent(variables[key])
+        );
+    }
+    return pathTemplate;
+};
+
+module.exports.map = function(array, fn) {
+    var results = new Array(array.length);
+    for (var i = 0; i < array.length; i++) {
+        results[i] = fn(array[i]);
+    }
+    return results;
+};
+
+module.exports.isFunction = function(value) {
+    return Object.prototype.toString.call(value) == "[object Function]";
+};
+
+module.exports.checkObjectHasKeys = function(obj, keys) {
+    for (var i = 0; i < keys.length; i++) {
+        if (!obj.hasOwnProperty(keys[i])) {
+            throw new Error("Missing required key: "+keys[i]);
+        }
+    }
+};
+
+module.exports.checkObjectHasNoAdditionalKeys = function(obj, allowedKeys) {
+    for (var key in obj) {
+        if (!obj.hasOwnProperty(key)) { continue; }
+        if (allowedKeys.indexOf(key) === -1) {
+            throw new Error("Unknown key: "+key);
+        }
+    }
+};