fix long line, break it up in pieces:

```python
install_cmd = "tar xfv Schrodinger_Suites_%(version)s%(versionsuffix)s.tar && "
install_cmd += "cd Schrodinger_Suites_%(version)s%(versionsuffix)s && "
install_cmd += "./INSTALL -d . -s %(installdir)s -k $TMP -t %(installdir)s/thirdparty -b * "
```