hdf5_ep

[svn-r24804] Description:
    Brought changes from Coverity branch back to trunk, and cleaned up misc.
other warnings & formatting issues:

r20833:
Fixed Coverity 667 and 668 with real integer overflow tests this time.

r20834:
Use HDstrncpy and HDstrncat. --gh 

r20835:
Change to use strncpy - use base_len + 1 for line 156, use HDstrlen(path) + 1 for line 159

r20836:
Fixed coverity 585 by casting output of fgetc() to a char.

r20837:
Changed sprintf calls to snprintf with size 1 less than the allocated buffer to address coverity issue #967.

Tested on:
    Mac OSX/64 10.9.2 (amazon) w/C++, FORTRAN & parallel
    (too minor to require h5committest)