hdf5_msb

[svn-r16815] Description:
    Added member function Attribute::getInMemDataSize(), which is a wrapper
    of several C calls, to simplify getting the attribute's data size in
    memory.  Used this new function in Attribute::read to get the fixed-len
    string attribute data.

    Added to tests in tattr.cpp.

Platforms tested:
    Linux/32 2.6 (jam)
    FreeBSD/64 6.3 (liberty)
    SunOS 5.10 (linew)