www/glassfish, www/glassfish5, www/glassfish4: Make glassfish5 the default

Copy the glassfish4 in www/glassfish to www/glassfish4 as a fallback for users
depending on glassfish4 and unable to switch to glassfish5.

Take maintainership of www/glassfish4

Move the content of www/glassfish5 to www/glassfish, thereby making glassfish5
the new default. The glassfish5 port has been around for 1.5 months now w/o
bugs reported.

Remove the www/glassfish5 port. Note in MOVED that it's now in www/glassfish.