hdf5doc

Description:
H5Pset_local_heap_size_hint.htm only
    Replaced visible note to the editor with formulas or values for 
        'size_hint' for groups with many members, few members, and 0 members.
        -- Closes Bugzilla entry 1509.
    Added "Motivation" heading and rewrote that text.

H5Pset_local_heap_size_hint.htm  and
H5Pget_local_heap_size_hint.htm 
    Restated "Purpose" to describe the need filled rather the function's 
        technical action.
    Other edits for format and clarity.
    Removed unused template material.
Tested:  Firefox