All: Avoid polluting errors reported on device disconnect

* Makes libusb_cancel_transfer not log an error when the cancel fails
  with LIBUSB_ERROR_NO_DEVICE, so that apps can properly clean things
  up on device disconnect without flooding the console with these errors.
* Also, some devices (Cypress FX) may switch VID:PID on the fly during
  firmware upload => reduce severity of the Windows message when that happens.

Conflicts:
	libusb/os/windows_usb.c
	libusb/version_nano.h
Core: Make libusb_error_name also handle transfer status codes

Note that for the code 0 which means success resp. completed we have an
overlap in the codes. This is not a problem since normally one would not
call libusb_error_name on success / normal completion.

Conflicts:
	libusb/core.c
	libusb/version_nano.h
Samples: Add fxload sample for Cypress EZ-USB chips

* This program was modified from the original fxload at:
  http://linux-hotplug.sourceforge.net to add libusbx
  as well as non HEX images support.
* Only supports RAM upload for now, with EEPROM and FX3
  support to be added at a later stage.

Conflicts:
	examples/Makefile.am
	libusb/version_nano.h
	msvc/ddk_build.cmd
	msvc/libusb_vs2010.sln
Samples: Fix compiler warnings in fxload

ezusb.c: In function  "ezusb_cpucs"
ezusb.c:163: warning: initialization discards qualifiers from pointer target type
ezusb.c: At top level:
ezusb.c:193: warning: no previous prototype for "parse_ihex"
ezusb.c:340: warning: no previous prototype for "parse_bin"
ezusb.c:377: warning: no previous prototype for "parse_iic"
ezusb.c: In function "ram_poke":
ezusb.c:451: warning: enumeration value "_undef" not handled in switch
ezusb.c:491: warning: passing argument 2 of "ezusb_write" discards qualifiers from pointer target type

Conflicts:
	libusb/version_nano.h
Misc: Fix missing files from dist package

Conflicts:
	Makefile.am
	libusb/version_nano.h
All: Replace malloc+memset with calloc

Conflicts:
	libusb/version_nano.h