Move clip selection to separate function

src/libexec/saturnin-clip

@@ -81,7 +81,8 @@ load_clip() {
     # Load single clip of choice
     #
     local clipname=$1
-    local name=$(saturnin clip ls | saturnin dmenu | cut -d\   -f 1)
+    local name=$(pick_clip)
+    test -n "$name" || return 1
     cat $STORAGE_DIR/$name | xclip -i -selection $clipname
 }
 
@@ -90,7 +91,8 @@ rm_clip() {
     # Remove single clip of choice
     #
     local clipname=$1
-    local name=$(saturnin clip ls | saturnin dmenu | cut -d\   -f 1)
+    local name=$(pick_clip)
+    test -n "$name" || return 1
     rm -f $STORAGE_DIR/$name
 }
 
@@ -104,6 +106,12 @@ rm_all() {
     rmdir "$STORAGE_DIR" 2>/dev/null | :
 }
 
+pick_clip() {
+    saturnin clip ls \
+      | saturnin dmenu \
+      | cut -d\   -f 1
+}
+
 
 clipname=primary
 action=list_nice