make file structure PSR-0 compatible

[caseycs]

move global constants to class, add gitignore

[romainneutron]

Great !

I think it's great to be PSR-0/1/2 compliant. One thing is disagree on this changes is the lack of support for PHP 5.2. I think we should not use namespaces, and probably move functions as methods of SphinxClient object.

Now, let's ping SphinxSearch developers and see how can it be maintained in the upcoming 2.0.7 versions and integrate SphinxSearch sources to ease the update of this repo.

[caseycs]

Good notices. I'll remove namespace. About functions - i agree, i'll move them.

[romainneutron]

For the record, I opened a thread on SphinxSearch forum : http://sphinxsearch.com/forum/view.html?id=10618

[atrauzzi]

Wondering when I can expect to see these changes in the master branch. The constants issue is a bit of a blocker for anyone trying to use this library properly.

[romainneutron]

This is not blocking as composer autoloads sphinxapi.php correctly. Using this PSR0 modified version would lead to another more blocking issue : re-do the job for every new Sphinx release.

As long as SphinxSearch php developers themselves do not use PSR-0 and avoid constants use, I'd rather prefer not to modify their jobs.

A workaround could be to create a branch in this project with tagged psr-0 versions of sphinx versions. Would it be a valid solution for you guys ?

[caseycs]

As for me - it will be great. We also can update readme.md, see commit below.

[atrauzzi]

The problem is that you can't resolve the constants without first triggering a load of the class. I'm just asking that commit 127c5ab be merged in and made available now as the current version that composer is pointing to is still using defines.

[KarelWintersky]

2019 year.
PHP 5.2 not supported more than 5 years ago.

I think, we CAN MERGE this PR now.