Update to upstream version 3.17

Details:

• bin/ntpshmmon is dependent on PPS option (see sConstruct)
• remove patch that has been upstreamed
• explicitly reference python2.7 rather than python2 (per current ports tree guidelines)
• use python flavors (Note: there is support for python3 in upstream. Reserving that change for a future update (as yet untested) )
• plist changes to reflect upstream changes: lib version bumps, added man page, removed a pkg-config file
• add X11 option for bin/xpgs*; update dependencies for 3.17 version of xgps* (needs python gi module & gtk3)

PR: 225310
Submitted by: z7dr6ut7gs@snkmail.com