Establish tokenizer objects for aggressive and conservative base tokenization

Change-Id: I702098185b0b6292c73217268d4516d55a2f95b5
diff --git a/.gitignore b/.gitignore
index 9071e73..b0955d2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,3 +6,4 @@
 *~
 .*
 !.gitignore
+/sandbox
\ No newline at end of file