Upgrade touch dependency.

The npm registry seems to have problems serving touch#0.0.2 (see https://github.com/npm/npm/issues/5636#issuecomment-49189798), which means that installing bower randomly fails. The v0.0.3 file doesn't seem to have this problem, so upgrade to that version. There is no functional difference between 0.0.2 and 0.0.3.