Ec2 spot price history library update bugfix

[ruecarlo]

Issue #, if available:

ec2-spot-price-history Jupyter notebook fixed:

• Updated libraries and kernel of the notebook. Previous kernel used had out-dated libraries that were causing issues
• Added functionality to dump all the historic prices to an excel spreadsheet (with tabs for each instance selected)
• Changed the re-sampling frequency from 5M to 1H

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