Update test script to use microkernel for testing
Update test script to use microkernel for testing

The test script was using an Ubuntu image by default.

This was problematic when their mirrors were getting
hammered during the precise release.

This commit updates the script to use something
much smaller.

ddepaoli3/fuel-library-dev,huntxu/fuel-library,eayunstack/fuel-library,ddepaoli3/fuel-library-dev,SmartInfrastructures/fuel-library-dev,stackforge/fuel-library,slystopad/fuel-lib,stackforge/fuel-library,zhaochao/fuel-library,eayunstack/fuel-library,stackforge/fuel-library,slystopad/fuel-lib,zhaochao/fuel-library,zhaochao/fuel-library,huntxu/fuel-library,xarses/fuel-library,ddepaoli3/fuel-library-dev,zhaochao/fuel-library,SmartInfrastructures/fuel-library-dev,eayunstack/fuel-library,Metaswitch/fuel-library,Metaswitch/fuel-library,SmartInfrastructures/fuel-library-dev,xarses/fuel-library,ddepaoli3/fuel-library-dev,zhaochao/fuel-library,slystopad/fuel-lib,eayunstack/fuel-library,SmartInfrastructures/fuel-library-dev,ddepaoli3/fuel-library-dev,xarses/fuel-library,xarses/fuel-library,Metaswitch/fuel-library,eayunstack/fuel-library,Metaswitch/fuel-library,huntxu/fuel-library,huntxu/fuel-library,SmartInfrastructures/fuel-library-dev,stackforge/fuel-library,slystopad/fuel-lib,huntxu/fuel-library