Allow passing multiple items to depri, like for the do command.

tests/t1700-depri.sh

@@ -6,7 +6,7 @@ test_description='basic depriority functionality
 
 test_todo_session 'depriority usage' <<EOF
 >>> todo.sh depri B B
-usage: todo.sh depri ITEM#
+usage: todo.sh depri ITEM#[, ITEM#, ITEM#, ...]
 === 1
 EOF
 
@@ -41,4 +41,31 @@ TODO: 1 deprioritized.
 TODO: 3 of 3 tasks shown
 EOF
 
+cat > todo.txt <<EOF
+(B) smell the uppercase Roses +flowers @outside
+(A) notice the sunflowers
+(C) stop
+EOF
+test_todo_session 'multiple depriority' <<EOF
+>>> todo.sh -p list
+2 (A) notice the sunflowers
+1 (B) smell the uppercase Roses +flowers @outside
+3 (C) stop
+--
+TODO: 3 of 3 tasks shown
+
+>>> todo.sh depri 3 2
+3: stop
+TODO: 3 deprioritized.
+2: notice the sunflowers
+TODO: 2 deprioritized.
+
+>>> todo.sh -p list
+1 (B) smell the uppercase Roses +flowers @outside
+2 notice the sunflowers
+3 stop
+--
+TODO: 3 of 3 tasks shown
+EOF
+
 test_done