A user was running into a problem where rbt was crashing with a

UnicodeError inside the SVN client when attempting to detect the

repository type. In their case, they weren't even using subversion, so

it was particularly silly.
While this can be worked around by setting REPOSITORY_TYPE, there's no

reason to log the "svn info" output during repo detection--either the

command returns success or error, and if it's an error, we know that

it's not a (working) subversion checkout. Not logging the output

insulates us from possible locale issues.

Ran unit tests.