Refactor PodCondition to PodPhase
Rename makeContainerKey -> make BoundPodsKey.

Fix some typos too.
Add helper for making simple selector.
Merge pull request #2522 from markturansky/v1beta3_podphaserefactor

Refactor PodCondition to PodPhase
Merge pull request #2525 from erictune/cleanup1

Rename makeContainerKey -> make BoundPodsKey.
Merge pull request #2526 from erictune/addhelper

Add selector making helper