Native TTS support (current for Windows only).

Additional information:

A new dynamic library `speechhlp_win32` project (standalone, using VC++) is introduced because using SAPI in MinGW is pain (no required headers).

Screenhots:
![image](https://f.cloud.github.com/assets/1398228/384602/86a9db0c-a65d-11e2-8e1f-8d85c5e1c7f7.png)

![image](https://f.cloud.github.com/assets/1398228/384610/cc426e0e-a65d-11e2-89f0-5616013d40be.png)