Adds comments to example contracts, improve example contracts documentation

[poppyseedDev]

Closes #555
Mentions #556

[poppyseedDev]

Note: there is a dead links error for https://github.com/zama-ai/fhevm/blob/main/examples/README.md, however this will not be an error anymore once this PR will be merged.

[jatZama]

Firstly, can you rebase interactively and squash all your commits to get a unique clean commit instead of 14?

[poppyseedDev]

Firstly, can you rebase interactively and squash all your commits to get a unique clean commit instead of 14?

@jatZama I managed to squash only a portion of them, for the remaining few I get the following error:

Unable to squash. Squashing replays all commits up to the last one required for the squash. A merge commit cannot exist among those commits.

[jatZama]

Firstly, can you rebase interactively and squash all your commits to get a unique clean commit instead of 14?

@jatZama I managed to squash only a portion of them, for the remaining few I get the following error:

Unable to squash. Squashing replays all commits up to the last one required for the squash. A merge commit cannot exist among those commits.

how do you do the squash?
I use git rebase -i HEAD~X where X is the number of commits i want to squash

request for re-review