Rename Residual to ResidualDigraph (#67)
The new name is more analogous to other adaptor names.

Greatly extend and improve the test file for adaptors (#67)

- Add concept checks for the alterable, extendable, erasable
and clearable adaptors.
- Add test cases for modifying the underlying graphs through adaptors
whenever it is possible.
- Check the conversions between Node, Arc and Edge types.
- Add more test cases for the adaptor-specific functions and maps:
enable(), disable(), status(), forward(), backward(), CombinedArcMap,
CombinedNodeMap, ResidualCapacity etc.
- Use checkGraphIncEdgeArcLists() to simplify the test cases for
undirected graphs.
- Add test cases that use static graph structure (GridGraph) with
several adaptors combined.
- Add comments for the test cases.

Rename Lp*/Mip* to *Lp/*Mip

Remove lp_ prefix from the solver's header name

Bypass warnings with gcc 4.3

Thorough redesign of the LP/MIP interface (#44)

- Redesigned class structure
- Redesigned iterators
- Some functions in the basic interface redesigned
- More complete setting functions
- Ray retrieving functions
- Lot of improvements
- Cplex common env
- CLP macro definition to config.h.in
- Update lp.h to also use soplex and clp
- Remove default_solver_name
- New solverName() function in solvers
- Handle exceptions for MipCplex test
- Rename tolerance parameter to epsilon
- Rename MapIt to CoeffIt
- Lot of documentation improvements
- Various bugfixes

Port LP and MIP solvers from SVN -r3509 (#44)

Add HAVE_LP and HAVE_MIP #defines

Ignore standard .m4 files

Merge