Document minimal CMake version and fix typos

[romanc]

Description

This PR documents the minimal CMake version in the project's README.md and fixes a couple of typos in comments. This is a follow-up from #39, which introduced the CMake-based install.

How Has This Been Tested?

N/A

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas: N/A
• I have made corresponding changes to the documentation: N/A
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules: N/A
• New check tests, if applicable, are included: N/A