Create a "How To" section in the documentation

[VictorNS69]

We should add a new section called "How To" to explain the deployment and the upgrade process of the Smart Contracts.

Some important aspects in this documentation are:

• Enumerate the steps involving the upgradeability
• Detailed explanation about "what are we doing this"

Also, it would be a good idea to explain the proxy pattern we are using (openzeppeling) and how we are using it in Alastria.

[alejandroalffer]

Minor update in README.md to explain upgradeability function in https://github.com/alastria/alastriaID-truffle-contracts/tree/howto-update

Do not close this issue without running the commands and get captures from each step, and explain Proxy Pattern

[rober12]

Repository Miragtion to https://github.com/alastria/alastriaID-hardhat-contracts/tree/master