Enforce encoding and line endings with .gitattributes

[szapp]

To ease collaboration and cross-platform development, it's a good idea to not rely on local git settings for line endings and encoding. Instead let's enforce them with a .gitattributes. szapp/patch-template offers a good baseline for Daedalus scripts.

[AmProsius]

We could also think about .editorconfig as an alternative: https://editorconfig.org/

[szapp]

I think we should add both.

[szapp]

In order to better compare with the test environment, I will go through with the encoding and carriage return changes (i.e. add a .gitattributes) to the master branch. Let's keep the issue open to add an .editorconfig later, as well.