Renaming of labels

[dmtr99]

I will add a function to rename the labels to the allowed characters.
if the first letter is a number, we will add _ before the label.
As this will be defined in a function, the rules can easily be changed.

https://lexikos.github.io/v2/docs/misc/Labels.htm

[andymbody]

Does this still need to be addressed?

[Banaanae]

Yes see #201

[andymbody]

@dmtr99 added the function to replace number prefixes for labels. But that is all that was done. Will address the other characters as well.

It will be fun... See comment here #201 (comment)