Refactor namespace/shortname parsing into own method

Allows you to more easily create a custom file loader with a custom
namespace syntax.
minor #1403 Refactor namespace/shortname parsing into own method (anlutro)

This PR was merged into the 1.15-dev branch.

Discussion
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Refactor namespace/shortname parsing into own method

I've written a custom file loader in order for the namespace syntax to match across different resource loading classes. To achieve this I have to replace the loadTemplate method, which includes a lot of logic. While this logic may not be likely to change anytime soon, I'd feel better if the namespace parsing was extracted into its own method so I can replace just that bit.

Commits
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9dd3bb8 Refactor namespace/shortname parsing into own method