Add dynamic imports to sharing policy when Import-Package absent.

Fixes an issue where dynamic package imports added to a woven class were not added to a subsystem's sharing policy
if the subsystem had no Import-Package header, resulting in a NoClassDefFoundError.

git-svn-id: https://svn.apache.org/repos/asf/aries/trunk@1449199 13f79535-47bb-0310-9956-ffa450edef68
Add tests for dynamic package imports in sharing policy when no Import-Package header.

git-svn-id: https://svn.apache.org/repos/asf/aries/trunk@1449200 13f79535-47bb-0310-9956-ffa450edef68