[gcompris] target activity: minor fix, no more display the previous answer in the points: question.

[Bruno Coudoin <bcoudoin src gnome org>]

commit d8d3bbf05e42fecc4a5bd4383e1e5f31e2a9dae2
Author: Bruno Coudoin <bruno coudoin free fr>
Date:   Thu Feb 2 22:58:54 2012 +0100

    target activity: minor fix, no more display the previous answer in the points: question.

 src/target-activity/target.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/target-activity/target.c b/src/target-activity/target.c
index da6bd9f..9fa7c3b 100644
--- a/src/target-activity/target.c
+++ b/src/target-activity/target.c
@@ -350,6 +350,7 @@ static void target_destroy_all_items()
   animate_item = NULL;
   answer_item = NULL;
   answer_string_index = 0;
+  answer_string[0] = 0;
   user_points = 0;
 
   speedRootItem = NULL;