Fixes/e utils pub chem fixes

Arvid, these two patches are the result of me sitting down with Gang (PubChem) and Christopher (E-Utils) from NCBI. One patch corrects the URL to use, where the code was using an unofficial (but working) URL before; it's now using the proper URL. The second ensures that we actually output the number of hits we really asked for, instead of 15 out  of 50 before.