Remove `set_angles_from_list`, `set_angles_from`, `set_qs_from_range` and tests associated

[bobleesj]

@sbillinge Can I remove these util functions from the package? Since @yucongalicechen has started writing docs and docstrings, thought it would be best to keep it as portable as possible. But, I have copied and pasted those test functions explicitly above.

Originally posted by @bobleesj in #198 (comment)

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Remove the functions provided in the issue attached.