hgweb: add index template to json/map
This template allows showing the list of all repos in an hgweb instance (in
hgwebdir mode) as json.
The test has "lastchange" globbed because hgweb uses here file modification
time and not the last commit time.
#require symlink
https://bz.mercurial-scm.org/1438
$ hg init
$ ln -s foo link
$ hg add link
$ hg ci -mbad link
$ hg rm link
$ hg ci -mok
$ hg diff -g -r 0:1 > bad.patch
$ hg up 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg import --no-commit bad.patch
applying bad.patch
$ hg status
R link
? bad.patch