Correct install path w/out KDE installed.

teprrr on IRC noticed that the DATA_INSTALL_PATH was set wrong in
CMakeLists.txt, when KDE4 was not found.

CMakeLists.txt

@@ -8,7 +8,7 @@ if (KDE4_FOUND)
   include(MacroLibrary)
   macro_optional_add_subdirectory(doc)
 else()
-   set(DATA_INSTALL_DIR  "${CMAKE_INSTALL_PREFIX}/apps" CACHE PATH "The parent directory where applications can install their data")
+   set(DATA_INSTALL_DIR  "${CMAKE_INSTALL_PREFIX}/share/apps" CACHE PATH "The parent directory where applications can install their data")
    set(BIN_INSTALL_DIR   "${CMAKE_INSTALL_PREFIX}/bin"  CACHE PATH "The install dir for executables")
 endif()