int size difference on different architectures

[tripish]

Really liked the idea of your interface, and wanted to use it on some projects where I'm using the Teensy. Found the library didn't work because the serial communication of the same example sketch was different on the Arduino and Teensy. Traced it to the Guino code, where int is used. The Arduino casts this as a 16-bit signed integer (int16_t) whereas the Teensy casts is as a 32-bit signed integer (int32_t). Replacing all occurrences of "int" with "int16_t" solved the problem. Wanted to mention it in case anyone want to use this on other platforms.

[gbmhunter]

All occurrences of non-fixed width integers should really be removed, they always cause portability issues!