The public header doesn't have to include a local dynamically created
header file from the autotools. This would break the usability of the
public header files.
The calculation of transaction ids did not ensure that the result
is always greater or equal zero. To avoid conflicts with the error
codes returned by coap_send(), the calculation now masks out the
lower half.
In preparation for changing the make buildsystem to a fully autotools
controlled system moving the core libcoap source files to a better logical
place.
All the library related header files moving to include/coap/ to get
all the public and local header files in a separate place. Also moving
the C source files of the libcoap library to the folder src/.