Ptests to dune, add rules for diffing

.gitignore

ptests/ptests.ml

tests/builtins/Longinit_sequencer.i

tests/builtins/big_local_array.i

tests/callgraph/function_pointer.i

tests/cil/change_formals.c

tests/cil/change_to_instr.i

tests/cil/cpu_b.c

tests/cil/mkBinOp.i

tests/cil/queue_ghost_instr.i

.../constant_propagation/introduction_of_non_explicit_cast.c

tests/fc_script/main.c

tests/float/absorb.c

tests/jcdb/jcdb.c

tests/journal/control.i

tests/journal/control2.c

tests/journal/intra.i

tests/libc/fc_libc.c

tests/misc/__fc_machdep_custom.h

tests/misc/add_assigns.i