use latest ZXing release (3.5.3)

Among other improvements, this release of ZXing fixes the brokenness of the
`--raw` option (added in 3.5.0, but broken for `PDF_417` and maybe other
barcode types). See my bug report and fix for that issue at
zxing/zxing#1682 and
zxing/zxing#1683.

setup.py

@@ -23,8 +23,8 @@
 
 
 def download_java_files(force=False):
-    files = {'java/javase.jar': 'https://repo1.maven.org/maven2/com/google/zxing/javase/3.5.2/javase-3.5.2.jar',
-             'java/core.jar': 'https://repo1.maven.org/maven2/com/google/zxing/core/3.5.2/core-3.5.2.jar',
+    files = {'java/javase.jar': 'https://repo1.maven.org/maven2/com/google/zxing/javase/3.5.3/javase-3.5.3.jar',
+             'java/core.jar': 'https://repo1.maven.org/maven2/com/google/zxing/core/3.5.3/core-3.5.3.jar',
              'java/jcommander.jar': 'https://repo1.maven.org/maven2/com/beust/jcommander/1.82/jcommander-1.82.jar'}
 
     for fn, url in files.items():