Add Qvitter and QvitterPlus

diff --git a/plugins/Qvitter b/plugins/Qvitter
new file mode 160000 (submodule)
index 0000000..2be23b4
--- /dev/null
+++ b/plugins/Qvitter
@@ -0,0 +1 @@
+Subproject commit 2be23b403879d2f04a00f401ead47f698ddfdff3

diff --git a/plugins/QvitterPlus b/plugins/QvitterPlus
new file mode 160000 (submodule)
index 0000000..0e98b2f
--- /dev/null
+++ b/plugins/QvitterPlus
@@ -0,0 +1 @@
+Subproject commit 0e98b2f2ea5dee9de86cc2a6333ed30b85de5369