Add the the str_before extra helper, it's the inverse of str_after

[afsardo]

Hello :)

This PR adds an extra string helper, str_before which is exactly the inverse of str_after.

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My use case was:

I have an invitation system where I want to create a user with just the email while creating it with a name.
So I would receive the email in the controller, "a.fsardo@gmail.com" and I wanted my user to be:

["name" => "a.fsardo", "email" => "a.fsardo@gmail.com"]

Which would be from str_before(request('email'), '@').

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Since Laravel already has a str_after, for me it made sense that this one would be a no-brainer addition.

Hope this is helpful if not at least it was fun, the process of contributing.

[brunogaspar]

The ModelMakeCommand.php changes are unrelated to this PR and are already part of another PR so you should remove the changes here.

[afsardo]

Yes it was my bad, didn't notice it would get added to the PR, was working on something else.

I removed those last 2 commits, which made no sense at all, good catch @brunogaspar

[pinguinjkeke]

What the difference between this method and standard strtok?
The realisation of this method can be just a redirect to strtok method instead of 10 lines of code.

[GlennBags]

Ditto, can do same with strstr() with before_needle = true.