main.c: Add old default to the skip funcs, add command line option

main.c: Add old default to the skip funcs, add command line option

After removing the gconf dependency it was not possible to
declare g_malloc, g_malloc0, strdup and other custom methods
as allocating functions. Add a --skip-funcs parameter that
allows to skip user passed functions in the strack trace
to make the callers show up as the one allocating.

--skip-funcs=FUNC can be used multiple times and all passed
function names will be added.

* src/main.c: Add new cli parameter
(initialize_skip_funcs): Add default + cli values to the skip_funcs
(main): Call new function