Allow a per-tree setting to specify the character encoding used by the source code.
Remove an assumption about how HTML encoding and character set encoding
interact at the possible loss of some efficiency.
Put a hard limit on search results to head off an easy DOS.
Oops: min, not max
Allow a per-tree setting to specify the character encoding.  Close #165
Merge branch 'master' into ui to get order search results pr 196

Conflicts:
	dxr/templates/layout.html
	format