erl_interface switch to ei for c node functions

[Michael Truog]

I found a problem in the implementation that differs from the
documentation (problem in R12B-5 to R13B01, at least) in:
erl_interface-3.6.2/include/ei.h: line 332-333

int ei_unpublish(ei_cnode* ec);
int ei_unpublish_tmo(const char *alive, unsigned ms);

the implementation should be:
int ei_unpublish(ei_cnode *)
int ei_unpublish_tmo(ei_cnode *, unsigned int)

as described in the documentation:
http://erlang.org/doc/man/ei_connect.html

despite the fact the tmo function is closer to the interface for:
int    erl_unpublish(const char *alive);

Not sure if there are more problems like this, that is the only one I
bumped into.

Thanks,
Michael