suggestion to update README

["Geronimo Ma. Hernandez" <geronimo013@gmx.com>]

Hello,

I used debian-cd from svn. Following the instructions from the README showed 
me, that any (private) task-file created after "make status" would not be 
used on "make packages".

For me it looks like, that "make status" creates the tasks-directory in the 
tmp-tree (copying the files from ./tasks) and "make packages" will only use 
the tasks from the tmp-tree.

I would find it helpfull, if the README could point out that behaviour (line 
109ff)

kind regards
Geronimo