added:

* coroutines
 * string
modified:
 * http: fixed a couple of bugs
 * strutils: renamed to os, it is now a header for some generic platform-indipendent code
 * tracelog: added option to not print newline at the end of a message + bug fixes

coroutine.c

@@ -0,0 +1,11 @@
+#include "coroutine.h"
+
+coroutine_t coInit() {
+    return (coroutine_t) {
+        .state = 0
+    };
+}
+
+bool coIsDead(coroutine_t co) {
+    return co.state == -1;
+}