[patch bugfix] Correct goods routing

[z9999]

This patch will fix two problems.
- We could transport goods from bus stop.
- When we removed a stop or an ext-stop, rebuild_destinations() wasn't called.

[Borgoth]

Seeing cargo on a non-cargo-supporting bus stop on that screenshot made me wonder, is the fix
a) preventing cargo appearing on a bus stop since it doesn't support cargo or
b) preventing goods from being picked up on a bus stop tile?
I'd assume A. Not that B is a good thing either imo.

[Dwachs]

Is this somehow related to this old discussion:

http://forum.simutrans.com/index.php?topic=961.0 ?

So the patch is somehow semi-considered 

[prissi]

Applied to trunk, thank you.

[z9999]

Sorry, prissi, your code is wrong.
If a convoi schedule is on tile A and I removed a stop on tile A.
This convoi becomes out of connection.
So, we must recalculate all schedule anyway.
It doesn't depend on enabled ware_type.


And also, I can't compile r2603, because of error.

===> CXX simhalt.cc
simhalt.cc: In static member function `static bool haltestelle_t::remove(karte_t*, spieler_t*, koord3d, const char*&)':
simhalt.h:213: error: invalid use of member `haltestelle_t::enables' in static member function
simhalt.cc:208: error: from this location
simhalt.h:213: error: invalid use of member `haltestelle_t::enables' in static member function
simhalt.cc:210: error: from this location
make: *** [simhalt.o] Error 1

[Dwachs]

should be corrected in 2604.