[postinst] Add Cydia finish:restart at the end of postinst.

postinst

@@ -1,9 +1,9 @@
 #!/bin/bash
-# due to some sort of unfortunate permission error created by an older build of cephei, and dpkg not
+# Due to some sort of unfortunate permission error created by an older build of Cephei, and dpkg not
 # really fixing them, we need to fix this ourselves
 chown -R root:wheel /Library/PreferenceBundles/Cephei.bundle
 
-# and these somehow became a directory instead of a symlink
+# These somehow became a directory instead of a symlink
 if [[ -d /Library/Frameworks/Cephei.framework ]]; then
 	rm -r /Library/Frameworks/Cephei.framework
 	ln -s /usr/lib/Cephei.framework /Library/Frameworks/Cephei.framework
@@ -18,3 +18,10 @@ if [[ -d /Library/PreferenceBundles/Cephei.bundle ]]; then
 	rm -r /Library/PreferenceBundles/Cephei.bundle
 	ln -s /Library/Frameworks/CepheiPrefs.framework /Library/PreferenceBundles/Cephei.bundle
 fi
+
+# Tell the package manager to restart system app (SpringBoard) after installation.
+cydia=($CYDIA)
+if [[ ${cydia[1]} -ge 1 ]]; then
+	echo "finish:restart" >&${cydia[0]}
+fi
+exit 0