Take nonstandard filenames into account

[BertalanD]

Some people put configurations that apply to both zsh and bash into separate files, and source these from both shells' configuration. One example is .config/aliasrc in Luke Smith's voidrice repo.

Solution 1: follow source and . statements in shell config files. This would not work if the repo root does not correspond to the home directory, as described in #11.

Solution 2: track filenames commonly used for this purpose, i.e. aliasrc, aliases etc. This would be easier to accomplish.

[Kharacternyk]

We're searching GitHub by filenames, not by full paths. Thus there's no problem with subdirectories. Searching for multiple filenames (e.g. bashrc and aliasrc) is possible, but I have no desire to implement it myself anytime soon.