Many doc improvements for Circulation (#175)

- More precise doc for members.
- Several doc fixes.
- Add doc for public types.
- Better formulations.
- Add useful notes to the problem description.
- Use supply instead of excess in the doc.
- Hide the doc of the traits class parameter.
- Use \tparam for template parameters.

INCLUDE_DIRECTORIES(${CMAKE_SOURCE_DIR})

LINK_DIRECTORIES(${CMAKE_BINARY_DIR}/lemon)

SET(DEMOS

  arg_parser_demo

  graph_to_eps_demo

  lgf_demo)

FOREACH(DEMO_NAME ${DEMOS})

  ADD_EXECUTABLE(${DEMO_NAME} ${DEMO_NAME}.cc)

  TARGET_LINK_LIBRARIES(${DEMO_NAME} lemon)

ENDFOREACH(DEMO_NAME)