Add headers differentiating .shrc & .profile
appease The Doctor (i.e., Homebrew)

His admonition follows:

    Warning: Some directories in your path end in a slash.
    Directories in your path should not end in a slash. This can break other
    doctor checks. The following directories should be edited:
        /usr/local/texlive/2012/bin/x86_64-darwin/

I.e., this commit only tweaks the path by removing the
trailing slash.
Erect welcome sign