Recent bsd.port.mk changes

[Sergey Matveychuk]

Joe Marcus Clarke wrote:
>>>+					if ${GREP} -q "^$${df}$$" ${PLIST}; then \

I'd like to remember you many ports have a dynamicly generating PLIST. 
And it generate in pre-install target that followed _after_ 
check-already-stage target. So we'll not have PLIST here.

I guess decision is to resort _INSTALL_SEQ targets for 
check-already-installed target followed pre-install target.
And may be some other targets need move between pre-install and install?

-- 
Sem.