Rename PluginConfigProvider to PluginConfigFactory.

The PluginConfigProvider was not a guice Provider. Since all classes
named like ...Provider do implement the Provider<T> interface from
guice, we can consider the naming of PluginConfigProvider as
inconsistent.

Change-Id: I83cbe47112865e293a7928b123d94d4b4a3839db
2 files changed