create verifiability docs

[chenchanglew]

create verifiability design docs.

[coveralls]

Pull Request Test Coverage Report for Build 3705131688

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 56.783%

---

Totals
Change from base Build 3704930658:	0.0%
Covered Lines:	3273
Relevant Lines:	5764

---

💛 - Coveralls

[nkcr]

All good, just make sure to be consistent with the formatting. Especially, please leave exactly one blank line before and after titles and figures.

[nkcr]

The grammar of some sentences are sometimes a bit off, but overall we get the idea 👍 .

We just miss a reference to this document in the sidebar.md, which is the menu of the documentation website, after that we can merge.

[si-co]

I had a partial look at the document. The content is very nice, but please fix formatting issues, try to keep short lines since is a markdown document, and fix spelling and grammar errors. If you're unsure about English I'm happy to discuss during one of our meetings.

[si-co]

Suggested change

	Verifiability is an important property to allows voters to check their vote has been cast unaltered, and that it has been registered correctly in the electronic ballot box.
	Verifiability is an important property that enables a voter to check that their vote has been cast unaltered, and that it has been registered correctly in the electronic ballot box.

[si-co]

What is (version num)? Before merging it would be nice to add it.

[si-co]

Also, avoid abbreviations such as didn't in formal documents.

[si-co]

is shown as follows is wrong, say either is as follows or is shown below, or something like that.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication

[nkcr]

Thanks 👍