Rename bashrc files to not be hidden

There's no reason to hide these, we always link to them anyway
Add gitignore for vim swap files
Add automatic check for files in tentacle dir

Added a check for a file named:
tentacle/bashrc_interactive_${PREHOSTNAME}
where PREHOSTNAME is eg. muon5 for muon5.npl.washington.edu
Add similar changes for login, once

See commit for bashrc_interactive