Mail: smtp pipelining support. Basically, this does the following two changes (and corresponding modifications of related code): 1. Does not reset session buffer unless it's reached it's end, and always wait for LF to terminate command (even if we detected invalid command). 2. Record command name as the first argument to make it available for handlers (since now we can't assume that command starts from s->buffer->start).

# disable { PAUSE ] hwcap for Sun Studio 11
hwcap_1 = OVERRIDE;