limit to known phases

[greencoloured]

I have found with pinto that unexpected packages were getting pulled.

For example, the following will pull in Dist::Zilla along with its dependency on Moose.

pinto pull -s test ETHER/Task-Weaken-1.06.tar.gz

The culprit appears to be a required packages getting added for the phase:

X_Dist_Zilla

This patch limits the packages pulled by pinto to a known phase: configure, runtime, build or test.

[greencoloured]

I can't say for sure that this is the correct approach for Dist::Zilla, I'm working on the assumption here that anything that Dist::Zilla actually wants used should appear in one of the standard phases.