feat(entities): add entities actions

[5im0n]

PR Checklist

Please check if your PR fulfills the following requirements:

• [X] The commit message follows our guidelines: https://github.com/ngneat/elf/blob/master/CONTRIBUTING.md#commit
• [x] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[X] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

First attempt to add Entities Action in Elf, related to the issue: https://github.com/ngneat/elf/issues/247

Issue Number: https://github.com/ngneat/elf/issues/247

What is the new behavior?

Does this PR introduce a breaking change?

[ ] Yes
[X] No

[NetanelBasal]

Let me know when I can recheck it, please.

[NetanelBasal]

@5im0n what's the status?

[mehmet-erim]

Is there any progress? @5im0n

[5im0n]

Hey @NetanelBasal,

I'm pretty busy right now, In my last commit 3 weeks ago, I added the unit test.

You can check the MR, I'll add the documentation after

[NetanelBasal]

You have TODOS in the code. No rush. I just wanted to know the status.