Absences electronic interventions in nature

Following a comment expressed in a post in the Arduino forum I wrote a patch on the source code of AFSoftSerial by Ladyada. This patch adds a distinct buffer for each serial input (instead of a static, shared buffer). It thus allows to have several inputs/outputs (rx/tx).

Attention:

1. Each serial input allocates a new buffer of 64 bytes.
2. The baudRate is static ie. shared among all channels
3. There is max. one buffer per pin, so it is not recommended to declare several AFSoftSerial objects with the same receivePin

Patch and new files are attached to this file.