Install docs into share/doc/ rather than include/

--- CMakeLists.txt.orig	2019-06-29 00:30:15 UTC
+++ CMakeLists.txt
@@ -335,7 +335,7 @@ include_directories(${CMAKE_SOURCE_DIR}/src)
 
 include_directories(${CMAKE_SOURCE_DIR}/src)
 
-if(CMAKE_BUILD_TYPE MATCHES "[dD]ebug")
+if(FALSE AND CMAKE_BUILD_TYPE MATCHES "[dD]ebug")
     set(qhull_CPP qhullcpp_d)
     set(qhull_SHARED qhull_d) 
     set(qhull_SHAREDP qhull_pd)
@@ -661,9 +661,9 @@ install(FILES ${libqhull_HEADERS}    DESTINATION ${INC
 )
 
 install(FILES ${libqhull_HEADERS}    DESTINATION ${INCLUDE_INSTALL_DIR}/libqhull)
-install(FILES ${libqhull_DOC}        DESTINATION ${INCLUDE_INSTALL_DIR}/libqhull)
+install(FILES ${libqhull_DOC}        DESTINATION ${DOC_INSTALL_DIR}/libqhull)
 install(FILES ${libqhullr_HEADERS}    DESTINATION ${INCLUDE_INSTALL_DIR}/libqhull_r)
-install(FILES ${libqhullr_DOC}        DESTINATION ${INCLUDE_INSTALL_DIR}/libqhull_r)
+install(FILES ${libqhullr_DOC}        DESTINATION ${DOC_INSTALL_DIR}/libqhull_r)
 install(FILES ${libqhullcpp_HEADERS} DESTINATION ${INCLUDE_INSTALL_DIR}/libqhullcpp)
 install(FILES html/qhull.man         DESTINATION ${MAN_INSTALL_DIR} RENAME qhull.1)
 install(FILES html/rbox.man          DESTINATION ${MAN_INSTALL_DIR} RENAME rbox.1)