add separation to precondition of Init
merge arguments and there preconditions for

peek abd poke
work on introduction
fix some fixmes
remove argument sections and merge with preconditions
Merge branch 'master' of github.com:jensgerlach/validation into jensgerlach-master

Conflicts:
	Reports/D4.2/D4.2.2-VV-Implementation/D4.2.2.pdf
Merge branch 'jensgerlach-master'