Add methods to manipulate Repl context

lib/cylon.js

@@ -150,13 +150,13 @@ Cylon.config = function(opts) {
  * @return {void}
  */
 Cylon.repl = function repl() {
-  var repl = new Repl(
+  var instance = new Repl(
     { prompt: "mcp > " },
     { robots: this.robots }
   );
 
-  repl.start();
+  instance.start();
-}
+};
 
 // Public: Halts the API and the robots
 //

lib/repl.js

@@ -53,3 +53,30 @@ Repl.prototype.start = function() {
     this.emit("reset");
   }.bind(this));
 };
+
+// add a value to the context
+Repl.prototype.addContext = function(key, value) {
+  this.context[key] = value;
+  this.repl.context[key] = value;
+};
+
+// remove a value from the context
+Repl.prototype.removeContext = function(key) {
+  delete this.context[key];
+  delete this.repl.context[key];
+};
+
+// set the context to the provided object
+Repl.prototype.setContext = function(object) {
+  _.each(this.context, function(value, key) {
+    if (this.context.hasOwnProperty(key)) {
+      this.removeContext(key);
+    }
+  }.bind(this));
+
+  _.each(object, function(value, key) {
+    if (object.hasOwnProperty(key)) {
+      this.addContext(key, value);
+    }
+  }.bind(this));
+};