clib2 Code

- The fscanf() family failed to parse and convert %f parameters correctly
if the respective number did not begin with a digit, but a decimal
point. Hence ".7" would not be processed, but "0.7" would.

c.lib 1.206 (24.4.2015)

- Reworked the __putc() and putc() macros to reference the 'c' input
parameter only once, and to be free of side-effects when tinkering
with the buffer position.

- isatty() had the __fd_lock() call in the wrong place, which could have
led to cleanup problems later.

- The close action in the stdio, socket and termios hook code now
also zaps the fd pointer itself after cleaning up the file descriptor
table entry.

- Removed the remains of all the stack extension and stack overflow/underflow
checking code. It never actually worked. The bit that does work is the stack
usage measurement code, plus the bit that sets up the the custom stack
according to local setting or by calling a query function.