Allow referencing the sh file via link

[kghmanuel]

Intent is to allow users to use a link to reference the sh file in /usr/bin instead of adding mlcp/bin to the PATH definition.

change in mlcp.sh:

< DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"/../
---
> DIR="$( cd "$( dirname "$(realpath $0)" )" && pwd )"/..

This would allow the following to work:

sudo ln -s /path/to/mlcp/bin/mlcp.sh /usr/bin/mlcp

Users can then do mlcp anywhere without changing PATH definition