Makefile: add wget portability variable - $(WGET)
add tertiary fallback for unavailable package files
fix bracketing of wget calls
cleanup after failed download
add package cdn fallback
Makefile: correctly escape urls for amazon services
additional information in the documentation
package libftdi: use config.guess
package libftdi: override libusb detection

Otherwise libusb will be detected on the build system and fail if
it isn't there.
package libftdi: fix usb detection override
package netcdf: add update script
package netpbm: add update script
update package sqlite
update package xapian-core
update package pango
update package cairo
update package harfbuzz
package qtbase: fix prls and other patches
update package fontconfig
update package jpeg