feature "git tag -r" to show tags and commits they are pointing to

Hi,

Currently there is no way you can get the commits your tags are
pointing to by using git tag.
The only way i found is to use rev-parse (which is by the way not
supported by the bash_completion)

It seems reasonable to have upper level command like:

$ git tag -r

to output

v0.1  8794hke84f9e8h9ef9eh949793...
v0.2  jhkd934398e9f499f47w9789o97...

$ git tag -n -r

v0.1 "super message"     8794hke84f9e8h9ef9eh949793...
v0.2  "another message" jhkd934398e9f499f47w9789o9f...

$ git tag -r v0.2
v0.2  jhkd934398e9f499f47w9789o9f...


What do you think?

Thanks,
Eugene