Update link in README from PR diff to repo code?

[iteles]

Found through review of #11

Link currently points to https://github.com/dwyl/phoenix-ecto-append-only-log-example/pull/2/files#diff-db55bfd345510f8bbb29d36daadf7061R21, which at the time was part of a PR.

Should we now update this to https://github.com/dwyl/phoenix-ecto-append-only-log-example/blob/3eb130e103cef05ef57e5d1fcd2a54c7b723597d/priv/repo/migrations/20180912142549_create_addresses.exs ?

[nelsonic]

@iteles great question!
The line you are referring to is:

In the context of the PR it shows that the whole migration file was created as part of that PR
and the line in question was added as part of the migration.

I agree that in this context, simply linking to the file (and not the PR) will be "less confusing" to people reading it. (they won't be scratching their heads wondering why ...)

Something we can do in the next iteration. 👍