Convert env to a list compatible with Galaxy job conf

[natefoo]

In Galaxy job destinations/environments, env is a list, where each element is a dict with one of three formats:

env:
  # becomes `FOO=foo; export FOO`
  - name: FOO
    value: foo
  # becomes `source /bar`
  - file: /bar
  # becomes `/baz`
  - execute: /baz

In TPV, env is instead a dict where keys are vars and values are their values. These are converted into a list of {"name": k, "value": v} dicts when the job destination is constructed. Because static destinations in the Galaxy job conf are no longer required as of TPV 2.0.0, it's desirable to be able to define destinations and complex envs fully in the TPV config.

This change supports the list syntax but is backwards compatible with the dict syntax. It overwrites any values on merging where names/keys match, and preserves the ordering of any existing env entries when merging. Any non-matching env entries are appended.

[coveralls]

Pull Request Test Coverage Report for Build 4137627996

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Details

• 14 of 14 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.05%) to 96.764%

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Totals
Change from base Build 3913663123:	0.05%
Covered Lines:	929
Relevant Lines:	952

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💛 - Coveralls

[nuwang]

This is great! @cat-bro and I discussed this today, and we too were thinking that supporting both syntaxes would be the best solution. The simple dict format is compact and easy for a majority of usecases, and the array syntax for more advanced cases.

[nuwang]

I think it would be better to move this to the constructor, at the point of first assignment?

total-perspective-vortex/tpv/core/entities.py

Line 193 in fadf3f6

self.env = env

[nuwang]

Looks great! Thanks for the fix. Let me know how urgently you need a release made.

[natefoo]

No rush, I can install the dev version. Thank you!