Added Pre built binaries.

We are now packaging and publishing binaries for:

1. Linux ia32 and x64
2. OSx 32 and 64 bit.
3 Win 32bit.

There is an issue with compiling the windows 64bit version of the binary in appveyor, it seems some libraries are missing for serialport to compile, hopefully they will have them sorted out sonner rather than later.

Thanks to everyone for comments and help in:
https://github.com/voodootikigod/node-serialport/issues/290

Specially to @springmeyer (since most of the code is based on his previous contributions) and to @BergWerkGIS since his code for appveyor.yml configuration and suggestions kickstarted the windows binaries packaging and publishing.