Added alphanumspace string validator

[haribabuk113]

Fixes Or Enhances

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• Tests exist or have been written that cover this particular change.

@go-playground/validator-maintainers

I’ve been using this package in several projects at our company. Yesterday, while searching for a validation tag that supports alphanumeric characters and spaces for Go structs, I was unable to find an existing one. To address this, I created a regex pattern that allows alphabets, numbers, and spaces.

This pull request adds that regex-based validation tag to the package, extending its functionality for common text fields requiring alphanumeric and space support.

Summary of Changes
Added a new regex validation tag supporting alphabets, numbers, and spaces

Included documentation and tests for the new tag

[coveralls]

coverage: 73.749% (+0.004%) from 73.745%
when pulling d94746d on haribabuk113:master
into 80b6d11 on go-playground:master.

[nodivbyzero]

this change is not needed anymore. Please rebase

[haribabuk113]

rebase is done.

[nodivbyzero]

Thank you for your contribution to the go-playground/validator project.

The changes look good.

Could you add a description of your validator to doc.go?
https://github.com/go-playground/validator/blob/master/doc.go

[haribabuk113]

Thank you for your contribution to the go-playground/validator project.

The changes look good.

Could you add a description of your validator to doc.go? https://github.com/go-playground/validator/blob/master/doc.go

Descritpion for his validator tag is added to doc.go

[nodivbyzero]

This change isn’t related to the alphanumspace string validator.
Could you please revert this file?

[haribabuk113]

This file has been reverted.