Skipping over LLVM debug info function calls.
Merge branch 'svcomp13' into ext
Implemented support for functions with variable number of arguments, and in particular for printf. Fixes #7.
Fixes a minor issues related to the fact that VERIFIER_nondet_int is a variable argument function since it is declared as extern.
Addressed another minor issues related to handling variable number of arguments functions. Fixes #7.