RFR 8171138: Remove FileCopierPlugin

[Mandy Chung]

> On Dec 14, 2016, at 9:02 AM, Sundararajan Athijegannathan <sundararajan.athijegannathan at oracle.com> wrote:
> 
> Please review http://cr.openjdk.java.net/~sundar/8171138/webrev.00/ for https://bugs.openjdk.java.net/browse/JDK-8171138
> 
> Piggybacking cleanup: release file generation ("TOP" entry type handling) moved to accept(ResourcePoolEntry)
> 

The removal of FileCopierPlugin looks fine.

The image builder writes out all entries from the ResourcePool.
`release` file is already an entry added to ResourcePool and the content
is known when the entry is created.  The image builder could just write out `release` file in the same way as all other entries (i.e. with ResourcePoolEntry::contents).  A related question is whether we want to keep TOP type going forward.  You could either leave the `release` file generation change out, leave it as is, or write the content when the entry is created in ReleaseInfoPlugin (i.e. storeRelease method can also be removed).

Mandy