* Use "|" as the separator between module path and name.
":" is already a path character in Windows. This is why the
dartdevc tests aren't working on Windows. Because they try to do:
-sC:/some/path/blah.dart:blah
And it splits at the first ":". Oops.
* Switch to "=" for separating module path from name.
It looks a little funny when used with "--summary=", but it works fine
and is very unlikely to be used for anything else on any platform
(since we already use it as the separator between arg name and value).
Bob Nystrom
7b17a3dd01