url: be stricter about detecting schemes
While the URL parser is very forgiving about what characters are
allowed in each component, it's useful to be strict about the scheme
so we don't accidentally interpret local paths with colons as URLs.
This restricts schemes to containing alphanumeric characters, dashes,
pluses, and dots (as specified in RFC 2396).
Test the CIA extension
$ cat >> $HGRCPATH <<EOF
> [extensions]
> hgcia=
>
> [hooks]
> changegroup.cia = python:hgext.hgcia.hook
>
> [cia]
> user = testuser
> project = testproject
> test = True
> EOF
$ hg init src
$ hg init cia
$ cd src
$ echo foo > foo
$ hg ci -Amfoo
adding foo
$ hg push ../cia
pushing to ../cia
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
<message>
<generator>
<name>Mercurial (hgcia)</name>
<version>0.1</version>
<url>http://hg.kublai.com/mercurial/hgcia</url>
<user>testuser</user>
</generator>
<source>
<project>testproject</project>
<branch>default</branch>
</source>
<body>
<commit>
<author>test</author>
<version>0:e63c23eaa88a</version>
<log>foo</log>
<files><file action="add">foo</file></files>
</commit>
</body>
<timestamp>0</timestamp>
</message>