Modify the interface of Suurballe (#266, #181)

- Move the parameters s and t from the constructor to the run()
function. It makes the interface capable for multiple run(s,t,k)
calls (possible improvement in the future) and it is more similar
to Dijkstra.
- Simliarly init() and findFlow(k) were replaced by init(s) and
findFlow(t,k). The separation of parameters s and t is for the
future plans of supporting multiple targets with one source node.
For more information see #181.
- LEMON_ASSERT for the Length type (check if it is integer).
- Doc improvements.
- Rearrange query functions.
- Extend test file.

prefix=@prefix@

exec_prefix=@exec_prefix@

libdir=@libdir@

includedir=@includedir@

Name: @PACKAGE_NAME@

Description: Library of Efficient Models and Optimization in Networks

Version: @PACKAGE_VERSION@

Libs: -L${libdir} -lemon

Cflags: -I${includedir}