Add tasks for all the new languages

Task/Dynamic-variable-names/Sidef/dynamic-variable-names.sidef

@@ -0,0 +1,10 @@
+var name = read("Enter a variable name: ", String);     # type in 'foo'
+
+class DynamicVar(name, value) {
+    method init {
+        DynamicVar.def_method(name, ->(_) { value })
+    }
+}
+
+var v = DynamicVar(name, 42);       # creates a dynamic variable
+say v.foo;                          # retrieves the value