remove disabled code in modulepaths.nim

[bung87]

Summary

Remove disabled code related to nimble in modulepaths, it was left
over from a long ago (6+ years) disabled import feature related to
nimble. Since we'll have a new package manager anyways, not bothering
to investigate it any further.

Details

• Remove constants considerParentDirs, considerNimbleDirs
• Remove procedures findInNimbleDir, resolveDollar,scriptableImport,
  lookupPackage
• Remove lookupPackage disabled usage in getModuleName

[saem]

@bung87 the long term plan is not for me to write all of your PR messages. Please look back at the changes I've made in previous PRs and clean-up this and all the other PRs.

[bung87]

I know that, but this is for clean up, I don't have much reason in my mind to be written.

[saem]

I know that, but this is for clean up, I don't have much reason in my mind to be written.

I know it's tempting, I feel the same way some times, but over and over again experience has shown that it doesn't pay off in this code base.

[saem]

Good job removing all this deadcode, @bung87

[saem]

/merge

[github-actions]

Merge requested by: @saem

Contents after the first section break of the PR description has been removed and preserved below:

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Notes for Reviewers

• Simplifies the code base