Added advice to avoid repeated Vagrant box downloads
Simplify changes to `.bashrc` in virtual environment

* Preparing to support running scripts in the Vagrant environment via
  `ssh`
Improvements to make `vagrant provision` run more reliably

* Check for existing version of `pip` to decide whether to use
  `--no-use-wheel` option
* Set $HOME in case it's used by any Python package installer (for
  example, pip's "wheel" uses it as `os.path.expanduser('~')`
Merge pull request #867 from reciprocity/feature/deployment-and-jenkins-updates

Feature/deployment and jenkins updates