Some improvements for next major release

[vansari]

I have seen your Repo and find it very useful. So I want to contribute some useful changes.

Changes:

• declare strict types
• Added Return Types
• Remove unnecessary consts
• use regex group name for more readability
• cast variables to string
• fixed compatibility for PHP < 8.0 with substr in strict mode

PR Description

Done some code styles fixes and a bugfix with PHP < 8.0 in strict type mode

Checklist

• I agree with the Code Contribution License Agreement in CONTRIBUTING.md

[codecov]

Codecov Report

Merging #21 (3d9206d) into next (8f0425c) will increase coverage by 0.66%.
The diff coverage is 94.73%.

❗ Current head 3d9206d differs from pull request most recent head 72eaa9d. Consider uploading reports for the commit 72eaa9d to get more accurate results

@@             Coverage Diff              @@
##               next      #21      +/-   ##
============================================
+ Coverage     94.11%   94.78%   +0.66%     
- Complexity      103      104       +1     
============================================
  Files             1        1              
  Lines           221      230       +9     
============================================
+ Hits            208      218      +10     
+ Misses           13       12       -1     

Impacted Files	Coverage Δ
src/Decimal.php	94.78% <94.73%> (+0.66%)	⬆️

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[dereuromark]

Thanks a lot for your contribution

Lets separate those into two different things:

• Bugfixes and BC improvements: master
• BC breaking changes and remove of deprecations etc: next

The next branch will then eventually become a new major version in the future.

I added this to the docs: https://github.com/spryker/decimal-object/blob/master/docs/README.md#contributing

[vansari]

@dereuromark So I have changed the target to next. I think this changes would be great :-)

[dereuromark]

Cool
But those string casts etc would be useful to have already for master, right?
You might want to extract those first into master, and then we can merge master + your additional changes into next.

[vansari]

I have updated the code. So the next release will support only PHP Versions > 8.0