Add a dynamic integration of srcML into the add_srcML function

[nalmadi]

The add_srcML currently uses pre-generated files for the EMIP dataset code. It does not generate srcML tags for any piece of code.

It would be great to integrate srcML into the tool so it is called automatically (behind the scene) to generate the srcML tags for any code, then add the tags to the dataframe.

This means that we will add srcML as a dependency, so let's see if we can do this in an easy way. Not sure if srcML is downloadable through pip or similar. This might create problems for our automated Action testing, if srcML is not downloadable through pip.

A good start would be at srcML website to understand the tool and how it works: https://www.srcml.org/