slapos-testing: add libnetworkcache egg as dependency.

buildout can be run and may need libnetworkcache in order to run tests (if zc.buildout.testing.buildoutSetUp() is called).
Revert "slapos-testing: add libnetworkcache egg as dependency."

This reverts commit 6909fe3b92a3abfc7f922c477458ff11fcab1187.
Use newer slapos.recipe.build (0.13) for gitclone.
version up : HAProxy 1.5.5.
version up eggs.