perform HTML escaping in diffline()
fixes #719
add comments
fix comments
input params comment
Merge pull request #720 from vladak/diffline

Diffline
first version of changeset search link in Annotate view
fixes #721
introduce method for getting revision ID out of revision ID from HistoryEntry suitable for annotate
fixes #722
use webapp prefix from runtime environment
Merge pull request #723 from vladak/search_link

Search link and annotate fixes