Unify annotated and non-annotated tags

Hi,

It is hard to work with Git tags, because on low level hash of non-annotated tag is pointing to commit, but hash for annotated tag is pointing to tag metadata.

On low level that means that there is no way to get commit hash from tag in a single step. If tag is annotated, you need to find and parse ^{} string of show-ref, if not, then look for string without ^{}.

So, why not just make all tags work the same so that every tag has its own hash and you need to dereference it in the same way to get commit hash?

This way I could get all commit hashes with just:

    git show-ref --tags -d | grep "\^{}"

or abandon ^{} completely and show commit hashes on -d:

    git show-ref --tags --dereference