Config unification

Replace Candlepin's Config class with Configuration from common. No more ```new Config()``` in mainline code, rely on injection of Configuration from Guice.

TEST
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Simply do what you normally do to use Candlepin.

NOTE: I did not update Gutterball.
Since when have we allowed using wildcards? http://www.candlepinproject.org/docs/candlepin/java_coding_conventions.html#qualified-imports