Do not split query strings on ; anymore.

Using `;` as a separator instead of `&` was allowed a long time ago,
but is now obsolete and actually invalid according to the 2014 W3C
recommendations. Even if this change is technically backwards-incompatible,
no real-world application should depend on broken behavior. If you REALLY
need this functionality, monkey-patch the _parse_qsl() function.

bottle.py

@@ -2585,7 +2585,7 @@ def parse_range_header(header, maxlen=0):
 
 def _parse_qsl(qs):
     r = []
-    for pair in qs.replace(';','&').split('&'):
+    for pair in qs.split('&'):
         if not pair: continue
         nv = pair.split('=', 1)
         if len(nv) != 2: nv.append('')