Add support for Solaris & Illumos etc. (*easy* fix, code suggestion within)

[jdrch]

Solaris and Illumos use Bash as the default shell. However, currently bash-it does not work as expected on them.

This can be fixed as described, tested, and confirmed here.

Here's what I suggest:

• In install.sh, check for $0STYPE of solaris*
• If $0STYPE is solaris*, then:
  • Backup ~/.profile to ~/.profile.bak
  • Comment out all uncommented lines in ~/.profile
  • Add the following lines to ~/.profile:

# if running bash
if [ -n "$BASH_VERSION" ]; then
    # include .bashrc if it exists
    if [ -f "$HOME/.bashrc" ]; then
    . "$HOME/.bashrc"
    fi
fi

# set PATH so it includes user's private bin directories
PATH="$HOME/bin:$HOME/.local/bin:$PATH"

• Continue the rest of the install.sh as usual.

[nwinkler]

Great suggestion - please feel free to provide a PR for this!