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

Fix the date field comment of graphToEps() output (#336)

Modify the header of scripts/bib2dox.py (#184)

Merge

Fix LpBase::addRow(Constr) (#334)

Merge bugfix #337