[e-acsl] universal quantifications done (including testing)

[e-acsl] do not stop anymore when detecting an invalid/unsupported annotation
[e-acsl] tests for invalid quantifications

[e-acsl] universal quantifiers over integers. Not yet finished: work only in some cases
[e-acsl] logic variables (required by univ quantif)

[e-acsl] update todo-list

[e-acsl] tests now independent of GMP version (but GMP still required)

[e-acsl] fixing bug with logic label Here and Post

[e-acsl] all tests are now executed with gcc
[e-acsl] fix bug with integer division and modulo
[e-acsl] untested support of most logic labels
[e-acsl]

[e-acsl] support of \at for stmt labels

[e-acsl] support of field accesses in logic
[e-acsl] support of array accesses (yet missing guards) in logic
[e-acsl] support of pointer dereferences (yet missing guards) in logic
[e-acsl] support of \null in logic