fix yahoo/mojito-cli#21 have `mojito doc` assume the common case

invoking `mojito doc` without further arguments in an application
directory assumes `mojito doc app <name>`, and uses the name in
the app's package.json for <name>.
invalid type test
add fixture
change import var name "resolve" to "path.resolve"
use path.basename of mojit name, since it may be a path
do not prefix destination since yuidocjs does that
add functional tests

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rename