Fixed HDFFV-8670 
*H5DSis_scale and other HL APIs do not null terminate string (and other issues)
Include plugin header change. H5PLextern.h and H5PLprivate.h have two opposing use cases, only the enum is common.

Tested: local linux and windows
Upgrade packaging process with cmake helper functions.

Tested: local linux
Added tests for HDFFV-8879
Fix a bug in multi VFD when the memb_addr in H5Pset_fapl_multi is passed
as NULL. The library is supposed in that case to equally divide the
address space among all members, but there was a bug causing an
overflow in the assignment.

tested with h5commitest
Update from 1.8 docs - docs team changes from last release
Define symbol for other compilers as nothing.
Tested: platypus
Changed the callback function integer type from INTEGER to INTEGER(C_INT) for portability, HDFFV-8909.
Snapshot version 1.9 release 197
Fix for hdffv-8855.
Fix fo HDFFV-8912
Purpose: Fixed HDFFV-8852
Description:
    H5F_ACC_CREAT was included in the C++ API while the C library doesn't
    allow it yet.  Possibly, in the future, but not now.  In addition, the
    two flags H5F_ACC_RDONLY and H5F_ACC_RDWR were missing from the
    documentation, causing confusion that appending is not supported.
Solution:
    - Removed H5F_ACC_CREAT from the function until the C library support it
    - Added H5F_ACC_RDONLY and H5F_ACC_RDWR to the comments to update the
      documentation
Platforms tested:
    Linux/ppc64 (ostrich)
    Linux/32 2.6 (jam)
    SunOS 5.11 (emu)
merge from trunk.
fix merge bug for loaded vol plugins.