Bump version: 1.2 release

Closes #8 (closed)

Type of changes

• Bug fix (non-breaking change fixing an issue)
• New feature (non-breaking change adding functionality)
• Refactoring (improving code structure without modifying functionality)
• Breaking change (a fix, addition, or removal that would change an existing functionality)
• New version Release

Implementation Checklist

• My code follows the code style of this project
• My change requires a change to the documentation
• I have updated the documentation accordingly
• I have added tests to cover my changes
• (New features and breaking changes) I have added new functional tests, or updated the existing one accordingly
• All new and existing tests are passing
• I have updated the CHANGELOG accordingly