Log Message:
tex-pdftex{,-doc}: update to 2018

add dependency on tex-dehyph

2018/09/19 Added --distilleropts optlist command line flag for
           options to be added to the distiller application;
           e.g. "-dCompatibilityLevel=1.5 -dNOSAFER".
           Removed uses of echo -n.
2018/09/24 Added -dCompatibilityLevel=15 into the distillerprog definition
           and removed quotes around execution of ${distillerprog} so it can
           contain options.