Rewrite .bashrc
Rewrite .bashrc

- Generate PS1 from a function
- Add current git branch to prompt
- Add last error status to prompt
- Other assorted changes

mincardona/mincardona-cfg,mincardona/mincardona-cfg,mincardona/mincardona-cfg,mincardona/mincardona-cfg,mincardona/mincardona-cfg