Remove plotly dependency

[georgemccabe]

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Describe the Task

Time Estimate

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Issues should represent approximately 1 to 3 days of work.

Sub-Issues

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• Add a checkbox for each sub-issue here.

Relevant Deadlines

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Funding Source

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Define the Metadata

Assignee

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Labels

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Milestone and Projects

• Select Milestone as a METplotpy-X.Y.Z version, Consider for Next Release, or Backlog of Development Ideas
• For a METplotpy-X.Y.Z version, select the METplotpy-X.Y.Z Development project

Define Related Issue(s)

Consider the impact to the other METplus components.

• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

Task Checklist

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• Complete the issue definition above, including the Time Estimate and Funding Source.
• Fork this repository or create a branch of develop.
  Branch name: feature_<Issue Number>_<Description>
• Complete the development and test your changes.
• Add/update log messages for easier debugging.
• Add/update unit tests.
• Add/update documentation.
• Add any new Python packages to the METplus Components Python Requirements table.
• Push local changes to GitHub.
• Submit a pull request to merge into develop.
  Pull request: feature <Issue Number> <Description>
• Define the pull request metadata, as permissions allow.
  Select: Reviewer(s) and Development issue
  Select: Milestone as the next official version
  Select: METplotpy-X.Y.Z Development project for development toward the next official release
• Iterate until the reviewer(s) accept and merge your changes.
• Delete your fork or branch.
• Close this issue.