Add MASVS-PRIVACY

[cpholguera]

After collecting and processing all feedback from the MASVS-PRIVACY Proposal we're releasing the new MASVS-PRIVACY category.

The main goal of MASVS-PRIVACY is to provide a baseline for user privacy. It is not intended to cover all aspects of user privacy, especially when other standards and regulations such as ENISA or the GDPR already do that. We focus on the app itself, looking at what can be tested using information that's publicly available or found within the app through methods like static or dynamic analysis.

While some associated tests can be automated, others necessitate manual intervention due to the nuanced nature of privacy. For example, if an app collects data that it didn't mention in the app store or its privacy policy, it takes careful manual checking to spot this.