[FW][IMP] inventory: flesh out accounting

[fw-bot]

Revision of Average inventory valuation cost method.
Task ID: #3255051

Summary

Hi! I'm newly assigned to the inventory scope and wanted to update this inventory valuation doc for Odoo 14 and elaborate the accounting concepts in layman's terms. If you are able to fact-check and expand on the accounting concepts, I would greatly appreciate it!

Other changes

• Add math formulas to elaborate the journal entry calculations about inventory valuation
• Add more headings for organization (because the document got LONG very quickly)
• Renamed headings to be action-oriented and sentence case
• Add external links to related docs
• Remove instances of "I", "our", "we" and other pronouns
• Rewritten for clarity (not brevity)

Things to look out for in the review

(in order of importance)

1. What do you think about the Anglo-Saxon section (lines 186-266)
2. Does the definition of AVCO make sense?
3. Are the accounting concepts clear & accurate?
4. Do math explanations make sense?
5. Can they be shortened a little?
6. How is the organization of examples?
7. Do intros of sections seem redundant?

This PR is intended to be FW ported

Forward-Port-Of: #6424
Forward-Port-Of: #4005

[robodoo]

Pull request status dashboard.

[fw-bot]

@Felicious @StraubCreative cherrypicking of pull request #4005 failed.

stdout:

Auto-merging content/applications/inventory_and_mrp/inventory/management/reporting/inventory_valuation_config.rst
Auto-merging content/applications/inventory_and_mrp/inventory/management/reporting/using_inventory_valuation.rst
CONFLICT (content): Merge conflict in content/applications/inventory_and_mrp/inventory/management/reporting/using_inventory_valuation.rst

stderr:

07:39:21.187278 git.c:463               trace: built-in: git cherry-pick 20bd9582b5753d2d9150703d6a8aaad14538c509
error: could not apply 20bd9582b... [IMP] inventory: expand on accounting and math
hint: After resolving the conflicts, mark them with
hint: "git add/rm <pathspec>", then run
hint: "git cherry-pick --continue".
hint: You can instead skip this commit with "git cherry-pick --skip".
hint: To abort and get back to the state before "git cherry-pick",
hint: run "git cherry-pick --abort".
----------
status:

Either perform the forward-port manually (and push to this branch, proceeding as usual) or close this PR (maybe?).

In the former case, you may want to edit this PR message as well.

More info at https://github.com/odoo/odoo/wiki/Mergebot#forward-port

[Felicious]

Hi @StraubCreative :D cherry-picked and resolved the merge conflict. all checks pass, we can try merging again

[StraubCreative]

@robodoo r+