Fixed Annis OR group (resolved #96)

Change-Id: I495c02cee0350315550420b5aa14cbc37e7b5b50
diff --git a/src/main/antlr/annis/AqlParser.g4 b/src/main/antlr/annis/AqlParser.g4
index f26eb9b..5718a77 100644
--- a/src/main/antlr/annis/AqlParser.g4
+++ b/src/main/antlr/annis/AqlParser.g4
@@ -191,5 +191,5 @@
 
 
 exprTop
-: andTopExpr (OR andTopExpr)* # OrTop
+: BRACE_OPEN? andTopExpr (OR andTopExpr)* BRACE_CLOSE? # OrTop
 ;
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