doc: put API table of contents in alphabetical order

doc/api/_toc.markdown

@@ -1,36 +1,36 @@
 * [About these Docs](documentation.html)
 * [Synopsis](synopsis.html)
-* [Globals](globals.html)
+* [Assertion Testing](assert.html)
-* [STDIO](stdio.html)
-* [Timers](timers.html)
-* [Modules](modules.html)
-* [C/C++ Addons](addons.html)
-* [Process](process.html)
-* [Utilities](util.html)
-* [Events](events.html)
-* [Domain](domain.html)
 * [Buffer](buffer.html)
-* [Stream](stream.html)
+* [C/C++ Addons](addons.html)
+* [Child Processes](child_process.html)
+* [Cluster](cluster.html)
 * [Crypto](crypto.html)
-* [TLS/SSL](tls.html)
+* [Debugger](debugger.html)
-* [String Decoder](string_decoder.html)
-* [File System](fs.html)
-* [Path](path.html)
-* [Net](net.html)
-* [UDP/Datagram](dgram.html)
 * [DNS](dns.html)
+* [Domain](domain.html)
+* [Events](events.html)
+* [File System](fs.html)
+* [Globals](globals.html)
 * [HTTP](http.html)
 * [HTTPS](https.html)
-* [URL](url.html)
+* [Modules](modules.html)
-* [Query Strings](querystring.html)
+* [Net](net.html)
+* [OS](os.html)
+* [Path](path.html)
+* [Process](process.html)
 * [Punycode](punycode.html)
+* [Query Strings](querystring.html)
 * [Readline](readline.html)
 * [REPL](repl.html)
-* [VM](vm.html)
+* [STDIO](stdio.html)
-* [Child Processes](child_process.html)
+* [Stream](stream.html)
-* [Assertion Testing](assert.html)
+* [String Decoder](string_decoder.html)
+* [Timers](timers.html)
+* [TLS/SSL](tls.html)
 * [TTY](tty.html)
+* [UDP/Datagram](dgram.html)
+* [URL](url.html)
+* [Utilities](util.html)
+* [VM](vm.html)
 * [ZLIB](zlib.html)
-* [OS](os.html)
-* [Debugger](debugger.html)
-* [Cluster](cluster.html)