Use target commands to specify include directories in ReSolve

[pelesh]

Currently ReSolve's root CMake file contains line setting:

include_directories(${CMAKE_SOURCE_DIR})

This specifies source directory as the build include directory. This should not be necessary as each ReSolve target already specifies include directories (both for build and installation). However, without this option set, CMake does not add correct include lines to the make files it generates.

It is unclear why is this happening. This also could be a bug in CMake. This needs to be further investigated.