vchoi_fork

[svn-r13979] purpose:
New feature.

Description:
Added routines to report on the amount of storage for:
1) 1.6 btree and heap storage info for groups
2) 1.8 btree, fractal heap storage info for groups, attributes and SOHM table
3) btree storage for chunked datasets
4) 1.8 superblock extension size.

Platform tested:
h5committested.