Renames version as run-version in shebang mode

[TekWizely]

Instead of just hiding the version command in shebang mode, I decided to rename it.

In regular mode, the command will still be available as version:

$ run -r my-runfile version

run v0.0.0

But it shebang mode, the command I will be available under run-version:

$ ./my-runfile-app run-version

run v0.0.0

This leaves your Runfile free to define its own version command

Runfile

version:
    echo "my-runfile-app v1.2.3"

output

$ ./my-runfile-app version

my-runfile-app v1.2.3

$ ./my-runfile-app run-version

run v0.0.0

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Fixes #18