Update release doc packaging script.

Improve how it deals with minor release bumps.
Be more aggressive with LSM throttling if checkpoints fall behind.
Don't pin chunks in cache when cursors are open on LSM trees.

We only need to hold the position while an update operation is in
progress.
Bump the primary chunk reference count before releasing the LSM lock.
Fix support for custom collators with LSM trees.
closes #544
Merge pull request #548 from wiredtiger/lsm-many-threads

Be more aggressive with LSM throttling if checkpoints fall behind. Don't pin chunks in cache just because cursors are open on LSM trees.
src/lsm/lsm_meta.c: function with return after a jump to an error label
Merge branch 'develop' into more-direct-io
Change the default page allocation size from 512B to 4KB, change the
maximum internal-node page size from 2KB to 4KB, attempting to avoid
likely direct I/O problems on Linux.   Ref #547.