Fix multiple execution bug in weighted matchings (#356)

This chgset also redoes the fix of [28c7ad6f8d91] and its backpont to 1.1,
[268a052c3043].

Add doc/references.dox to .hgignore

Replace figure at matching doc #348

The original bibartite_matching.eps is kept for future use.

Rename min mean cycle classes and their members (#179)
with respect to the possible introduction of min ratio
cycle algorithms in the future.

The renamed classes:
- Karp --> KarpMmc
- HartmannOrlin --> HartmannOrlinMmc
- Howard --> HowardMmc

The renamed members:
- cycleLength() --> cycleCost()
- cycleArcNum() --> cycleSize()
- findMinMean() --> findCycleMean()
- Value --> Cost
- LargeValue --> LargeCost
- SetLargeValue --> SetLargeCost

Fix gcc 3.3 compilation error (#354)

gcc 3.3 requires that a class has a default constructor if it has
template named parameters. (That constructor can be protected.)

Clarify type names in NetworkSimplex (#353)

This patch clarifies the misleading effects of the renamings
in [f3bc4e9b5f3a].

Merge #306

Add tolerance() functions for HaoOrlin (#306)

Merge #301

Also test fullInit() in suurballe_test (#181, #323)

Add traits class + named parameters to Suurballe (#323)

The following types can be modified using named parameters:
- FlowMap
- PotentialMap
- Path
- Heap + HeapCrossRef

Merge #181, #323

Rename heap structures (#301)

- KaryHeap --> DHeap
- FouraryHeap --> QuadHeap
- BinomHeap --> BinomialHeap

Add a fullInit() function to Suurballe (#181, #323)
to provide faster handling of multiple targets.
A start() function is also added, just for the sake of
convenience.

Rework and improve Suurballe (#323)

- Improve the implementation: use a specific, faster variant of
residual Dijkstra for the first search.
- Some reorganizatiopn to make the code simpler.
- Small doc improvements.

Remove unnecessary integer requirement in Suurballe (#323)

Bug fix in Suurballe (#323)

Configurable glpk prefix in ./scripts/bootstrap.sh and ...
unneeded solver backends are explicitely switched off with --without-*

Merge #342

Improve README and mainpage.dox (#342)

Merge #347

Use 'long long' flow cost in dimacs-solver.cc (#347)

Merge

Support tolerance technique for BellmanFord (#51)

A new operation traits class BellmanFordToleranceOperationTraits
is introduced, which uses the tolerance technique in its less()
function. This class can be used with the SetOperationTraits
named template parameter.

Merge #332

ArgParser can throw exception instead of exit(1) (#332)

Better return type for cycleLength() functions (#179)
in the min mean cycle algorithms.

The original Value type is used instead of the LargeValue type,
which is introduced for internal computations.

Merge #340

New heuristics for MCF algorithms (#340)
and some implementation improvements.

- A useful heuristic is added to NetworkSimplex to make the
initial pivots faster.
- A powerful global update heuristic is added to CostScaling
and the implementation is reworked with various improvements.
- Better relabeling in CostScaling to improve numerical stability
and make the code faster.
- A small improvement is made in CapacityScaling for better
delta computation.
- Add notes to the classes about the usage of vector<char> instead
of vector<bool> for efficiency reasons.

Merge bugfix #336