Use new version of Ipopt 3.11.7
Fixes for Windows build

- Use -lopenblas instead of -llibopenblas, the former works on both MinGW and Cygwin while the latter only works on MinGW
- Replace ../../psopt-installer-master with actual location of patches in $PSOPT_BUILD_DIR
- Add PSOPT=../.. to final make install invocation, so Makefile_include.mk can be successfully located
Merge pull request #1 from tavert/devel

Fixes for Windows build
Accepted in branch devel.
Compile Lusol without unpacking Psopt
Use Scotch instead of Metis for usage in Mumps.
Update Windows Installer to Ipopt 3.11.7
Merge branch 'master' into devel (Ipopt 3.11.7 integration)

Conflicts:
	COPYING
	LICENSES/LICENSE_Metis
	LICENSES/README
	wmpis.sh