This patch gets the newlib standard stream descriptors playing well with the
lwip socket descriptors and the spiffs file descriptors. The LWIP_SOCKET_OFFSET
is now defined to be 3, rather than zero, to avoid clashing with the standard
stream descriptors, and the SPIFFS_FILEHDL_OFFSET is bumped up to start after
the lwip descriptors.
mbedTLS version 2.1.0 (current stable)
Has some known issues/hacks:
* Entropy source not hooked in at all
* Linker script has a messy hack in it to store some (not all) data in
irom