Format 3 Version tag

[Noam-Dori]

Feature: Support for the "compatibility" attribute in version tags.

Background Format 3 introduces the "compatibility" tag which is used to guarantee support for packages built against older versions of the package.

Details

• [x] Add new attribute "compatibilty" with completion to version tag.
• [x] completion & annotations for attribute value are the same as the version value.
• [x] new annotation makes sure version compatiblity is smaller than version value
• [x] when the format is lower than 3 and the attribute is used, add an inspection that suggests upgrading to format 3