Security fix for CVE-2017-2586, CVE-2017-2587 and CVE-2017-5849,

—-

Add license information file copyright_summary

—-

New version of netpbm is available (10.77.00)

—-

add missing directives about bundled libraries jasper and jbigkit

—-

New version of netpbm is available (10.76.00)