Description: Restore 6 old error API functions back to the library to be backward
compatible with v1.6. They are H5Epush, H5Eprint, H5Ewalk, H5Eclear, H5Eset_auto,
H5Eget_auto. These functions do not have error stack as parameter.
Solution: Internally, these functions use default error stack.
Platforms tested: h5committest and fuss.
Misc. update: RELEASE.txt