Adding apache-snapshots as a plugin repo

A couple of plugins depend on jclouds-resources
Overriding modernizer-plugin exclusion file location for jclouds-project

Needs to use the local exclusions file, not the one from the
jclouds-resources dep (which is not present in jclouds-project)
JCLOUDS-153 Remove deprecated ExecutorService and HttpAsyncClient accessors.
fix checkstyle
JCLOUDS-40 Replaced incorrect use of @ConfiguresRestClient and deleted old rest client modules.