chicken_install.bbclass: use egg tarballs
chicken_install.bbclass: use egg tarballs

chicken_install.bbclass now uses egg tarballs instead of fetching egg
sources with chicken-install.

Signed-off-by: Mario Domenech Goulart <addb47291ee169f330801ce73520b96f2eaf20ea@ossystems.com.br>

OSSystems/meta-chicken,OSSystems/meta-chicken,OSSystems/meta-chicken