Use AsNoTracking in all EF reads

[wjonesy]

Summary of the changes (Less than 80 chars)

• Add .AsNoTracking() method to all db read queries
• Slight improvement to some select statements to only bring the data needed back from the database.

#126

[dnfclas]

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[dnfclas]

@wjonesy, Thanks for signing the contribution license agreement so quickly! Actual humans will now validate the agreement and then evaluate the PR.
Thanks, DNFBOT;