Fix issue with node changing every checkin

git-rev-parse will give you the hash of the tag object itself rather than the commit it points to by default. Using `tag^0` will return the actual commit.

`````
$ git rev-parse 0.0.152
238cc0ee29ada7069778d3711084b81b8a0ffbaa
$ git rev-parse 0.0.152^0
e6911e9ee1d589b8192ec2f6bbb6edc396ad5c2b
$ git rev-parse 0.0.152^{commit}
e6911e9ee1d589b8192ec2f6bbb6edc396ad5c2b
`````