Created a separate category for PHP Conferences

Outdated

Remove `Nomad PHP` YouTube channel

Remove `Nomad PHP` YouTube channel as it is not updated and `nomadphp.com` website is also in the Web Sites section.

Added Bugsnag to Debugging / Profiling

* Create a separate category for error tracking services

Created a separate category for error tracking services and added several popular tools to it.

* Sort items

* Update table of contents

* Fix names

* Update README.md

add ddev and devilbox to development environment

* add docksal to Development Environment

* Update README.md

* Update README.md

* Change order

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Co-authored-by: Alexander Kartavenko <askemailbox@gmail.com>

Change `Elephant.io` url to the fork as the original repo is no longer maintained.

Change `wordpress.org` url to GitHub repo url as it makes workflow fail

Remove `Qafoo/QualityAnalyzer`

The project is not maintained.

Add PHP Magic Number Detector (`povils/phpmnd`)

Adds hollodotme/fast-cgi-client to list of event libraries

Added TCPDF PDF generation library.

Co-authored-by: Povilas Susinskas <povilas.susinskas@gmail.com>

Remove Goutte

This library is deprecated.

Add CrawlerDetect

Remove `7php.com`

Not updated.

Remove `phpversions.info`

This site is no longer maintained.

Remove `phpsecurity`

Outdated, not maintained

Remove `phpbestpractices.org`

Outdated

Add a link to Unit Testing Tips

Remove `danielstjules/pho`

It doesn't support PHP 8 and isn't maintained.

Remove `peridot-php/peridot`

It doesn't support PHP 8 and isn't maintained.

Remove `HTTP Mock`

It doesn't support PHP 8 and isn't maintained.

Added Nette Tester to Testing section

Package is abandoned

* Add WsdlToPhp/PackageGenerator

* Remove `wsdl2phpgenerator` as it is no longer maintained

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Co-authored-by: Alexander Kartavenko <askemailbox@gmail.com>