biology/molden: Unbreak build; Correct WWW

For unbreak:

• pass FFLAGS to the build
• fix several errors in C
• remove the failing 'ex' command from makefile

Reported by: fallout
Approved by: portmgr (unbreak)

(cherry picked from commit 328d02d88e00267338e1a266aafb94f27827f4b3)