Add doc as root CMake subdirectory, do not always generate the man page.

CMakeLists.txt

@@ -193,4 +193,5 @@ ENDIF(WIN32)
 ADD_SUBDIRECTORY(src)
 ADD_SUBDIRECTORY(include)
 ADD_SUBDIRECTORY(tools)
+ADD_SUBDIRECTORY(doc)
 ADD_SUBDIRECTORY(unitTesting)

cmake @ 597d697c

-Subproject commit ce8da4f4399e3bef0c3cd825083fa350e906c7c4
+Subproject commit 597d697c4ee6f9bd4254360d9efaea15e41de340

doc/CMakeLists.txt

@@ -17,9 +17,7 @@ INCLUDE(../cmake/man.cmake)
 
 IF(UNIX)
   # Add `man' target.
-  ADD_CUSTOM_TARGET(
-    man ALL
-    DEPENDS dg-shell.1.gz dg-shell-plugin.1.gz)
+  ADD_CUSTOM_TARGET(man DEPENDS dg-shell.1.gz dg-shell-plugin.1.gz)
 
   # Man page generation.
   MANPAGE(dg-shell)