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

Update lemon/adaptors.h's header to 2009

Remove non-checked subgraph adaptors + rename parameters (#67)

Rename convenience functions in subgraph adaptors (#67)

- Rename hide(), unHide() to disable(), enable().
- Add new set function status(Item, bool).
- Remove hidden() and add status() instead
(which returns the opposite value).

Various doc improvements for graph adaptors (#67)

- Add notes about modifying the adapted graphs through adaptors
if it is possible.
- Add notes about the possible conversions between the Node, Arc and
Edge types of the adapted graphs and the adaptors.
- Hide the default values for template parameters (describe them
in the doc instead).
- More precise docs for template parameters.
- More precise docs for member functions.
- Add docs for important public typedefs.
- Unify the docs of the adaptors.
- Add \relates commands for the creator functions.
- Fixes and improvements the module documentation.