Add java_import_external maven_jar compatibility
Add java_import_external maven_jar compatibility

A alias() rule is now generated so the old @foo//jar label style can
still be used.

Fixes #200

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155204773

gramic/rules_closure,bazelbuild/rules_closure,jart/rules_closure,gramic/rules_closure,bazelbuild/rules_closure,bazelbuild/rules_closure,gramic/rules_closure,jart/rules_closure,jart/rules_closure,bazelbuild/rules_closure,gramic/rules_closure,jart/rules_closure,jart/rules_closure