gh-66 detect ycsb home using CHANGELOG

distribution/src/main/bin/ycsb

@@ -55,9 +55,10 @@ def find_jars(dir):
     return jars
 
 def get_ycsb_home():
-    bin_dir = os.path.abspath(os.path.dirname(sys.argv[0]))
-    ycsb_home = os.path.join(*([bin_dir] + [os.path.pardir] * 4))
-    return os.path.abspath(ycsb_home)
+    dir = os.path.abspath(os.path.dirname(sys.argv[0]))
+    while "CHANGELOG" not in os.listdir(dir):
+        dir = os.path.join(dir, os.path.pardir)
+    return os.path.abspath(dir )
 
 def get_command():
     if len(sys.argv) < 2: