Remove HAVE_CONFIG_H check

Remove HAVE_CONFIG_H check

config.h should always be included, a build without it never happens.
The checks on Linux always succeed, because autotools automatically
defines HAVE_CONFIG_H on all the Makefiles. On Windows this is not the
case. Removing all the checks revealed that multiple projects did not
include config.h because HAVE_CONFIG_H wasn't defined. This was the case
for at least the following projects:
- acyclic
- bcomps
- ccomps
- dijkstra
- ingraphs
- gc
- gml2gv
- graphml2gv
- gv2gml
- gvcolor
- gvgen
- mm2gv
- nop
- pathplan
- rbtree
- sccmap
- topfish
- tred

Added `windows\include` to the additional include directories and adding
some library paths solves some, but not all problems that emerged when the
check was removed and some code actually got compiled that wasn't compiled
before.