Coord bugfix

[jmcvey3]

• Fixes bug in coordinate determination for ADV amplitude and correlation measurements
• Fixes bug in coordinate determination for RDI bottom track amplitude and correlation measurements
• Removes time unit from gps time variable to avoid xarray encoding error.

Solves #96

[coveralls]

Pull Request Test Coverage Report for Build 2164254832

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 5 of 5 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.004%) to 90.737%

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Totals
Change from base Build 2059910008:	0.004%
Covered Lines:	4643
Relevant Lines:	5117

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💛 - Coveralls