Don't try to run non-python files

[cimnine]

Related Issue: N/A

New Behavior

During the startup scripts phase only files who's names end in .py are now executed.

Contrast to Current Behavior

Currently all files in the startup_scripts will be executed, regardless whether they are Python files or not. This leads to errors during startup if a non-python file happens to be in the respective directory. (e.g. desktop.ini or .DS_Store).

Discussion: Benefits and Drawbacks

I think it is valid to have non-python files in the startup_scripts folder. This may not even be intentional, but something your operating system did for your. Therefore the scripts should only try to run *.py files instead of any file in the startup_scripts directory.

Changes to the Wiki

n/a

Proposed Release Note Entry

Non-Python files are not considered as startup_scripts #307

During startup, only the startup_scripts who's filenames end in *.py will be executed.
Previously, all files would be interpreted as Python files.
This has led to unintentional behaviour.

Double Check

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