templater: complain about invalid application of '%' operator (BC) Before, '{x % y % z ...}' was silently evaluated as '{x % y}'. We no longer need this hack since the web template bugs was fixed by earlier patches. At this point, the error message may contain '<generator *>', which will be fixed later.

hgweb: fix type of {nav} keyword when linerange filter is active Spotted by making '%' operator check the operand type more strictly. Before, "{nav}" would be evaluated to a lazy "" (empty string) and {"" % x} would yield one empty string.

hgweb: fix {diff} expansion in JSON template The same sort of bug as the previous patch. In this case, I decided to fix the JSON template since we aren't ready to fix the {diff} keyword without BC. I'll rework it later.