OS X: Improve installer

This should mostly fix #2105 and #2044

admin/osx/CMakeLists.txt

@@ -13,3 +13,4 @@ endif()
 
 configure_file(create_mac_pkg.sh.cmake ${CMAKE_CURRENT_BINARY_DIR}/create_mac.sh)
 configure_file(macosx.pkgproj ${CMAKE_CURRENT_BINARY_DIR}/macosx.pkgproj)
+configure_file(pre_install.sh.cmake ${CMAKE_CURRENT_BINARY_DIR}/pre_install.sh)

admin/osx/macosx.pkgproj

@@ -471,13 +471,18 @@
 			</dict>
 			<key>PACKAGE_SCRIPTS</key>
 			<dict>
-				<key>POSTINSTALL_PATH</key>
-				<dict/>
-				<key>PREINSTALL_PATH</key>
-				<dict/>
-				<key>RESOURCES</key>
-				<array/>
-			</dict>
+                 <key>POSTINSTALL_PATH</key>
+                 <dict/>
+                 <key>PREINSTALL_PATH</key>
+                 <dict>
+                         <key>PATH</key>
+                         <string>@CMAKE_CURRENT_BINARY_DIR@/pre_install.sh</string>
+                         <key>PATH_TYPE</key>
+                         <integer>0</integer>
+                 </dict>
+                 <key>RESOURCES</key>
+                 <array/>
+         </dict>
 			<key>PACKAGE_SETTINGS</key>
 			<dict>
 				<key>AUTHENTICATION</key>

admin/osx/pre_install.sh.cmake

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+# kill the old version. see issue #2044
+killall @APPLICATION_EXECUTABLE@
+
+# Unload the Finder plugin. see issue #2105
+killall Finder
+