Generalization

[jinhan]

I changed to use env variables for the generalization.

Need to add new variables in secrets localxx.sh:

export PPROGRESS_DATASETS='{"h01_full0_v2": "https://local.brain-wire-test.org/segmentation/1.0/h01_full0_v2/", "test0_parents_v0": "https://local.brain-wire-test.org/segmentation/1.0/test0_parents_v0/" }'
export PPROGRESS_SERVER_ADDRESSES='{"h01_full0_v2": "https://local.brain-wire-test.org", "test0_parents_v0": "https://local.brain-wire-test.org" }'

Need to add new variables under env in kubetemplates/pprogress.yaml:

- name: PPROGRESS_DATASETS
  value: '${PPROGRESS_DATASETS}'
- name: PPROGRESS_SERVER_ADDRESSES
  value: '${PPROGRESS_SERVER_ADDRESSES}'