Buildsystem: Clean up build-process on all platforms

- Windows: Use CMAKE_INSTALL_PREFIX as a 'final install' directory (thanks to paradox for the preload-handling)
  (New target INSTALL, -not- included as part of ALL_BUILD (must be specifically run for installation to start)
- All: Build libmpq library (used for tools)
- All: Build extractiontools with hardlinked mpq-library (no need to install it anymore)
- All: Move jemalloc from being harddefined to using a CMake string (fixes issue 3378) (thanks to tru.bazoozoo for the idea, alternative added)

--HG--
branch : trunk

src/tools/vmap3_assembler/CMakeLists.txt

@@ -23,6 +23,8 @@ add_definitions(-DNO_CORE_FUNCS)
 
 add_executable(vmap3assembler VMapAssembler.cpp)
 
+add_dependencies(vmap3assembler mpq)
+
 if(WIN32)
   target_link_libraries(vmap3assembler
     collision
@@ -39,4 +41,6 @@ endif()
 
 if( UNIX )
   install(TARGETS vmap3assembler DESTINATION bin)
+elseif( WIN32 )
+  install(TARGETS vmap3assembler DESTINATION "${CMAKE_INSTALL_PREFIX}")
 endif()