Clarify ISSUE_TEMPLATE, ensure SHA is recorded

* Change "Make sure you have provided the following information" to
  "Confirm the following are included in your repo, checking each box".
  "Make sure" makes it seem like the checklist is provided for your
  convenience, if you want to use it. [I don't think that's the case](rhboot#203 (comment)).
* Move the "link to your branch" to a full question
  - Remove the "in the form user/repo@tag". It seems okay
    [when people don't use that format](rhboot#233 (comment)).
    That also doesn't work for non-github repos.
  - Add an example github url, to help communicate precisely what's
    wanted.
* Add a question about the SHA256 to make sure that submitters changing
  the tag can't change the binary without setting off flags.

ISSUE_TEMPLATE.md

@@ -1,6 +1,5 @@
-Make sure you have provided the following information:
+Confirm the following are included in your repo, checking each box:
 
- - [ ] link to your code branch cloned from rhboot/shim-review in the form user/repo@tag
  - [ ] completed README.md file with the necessary information
  - [ ] shim.efi to be signed
  - [ ] public portion of your certificate(s) embedded in shim (the file passed to VENDOR_CERT_FILE)
@@ -9,3 +8,13 @@ Make sure you have provided the following information:
  - [ ] any extra patches to grub via your own git tree or as files
  - [ ] build logs
  - [ ] a Dockerfile to reproduce the build of the provided shim EFI binaries
+
+-------------------------------------------------------------------------------
+### What is the link to your tag in a repo cloned from rhboot/shim-review?
+-------------------------------------------------------------------------------
+`https://github.com/user/shim-review/tree/myorg-shim-arch-YYYYMMDD`
+
+-------------------------------------------------------------------------------
+### What is the SHA256 hash of your final SHIM binary?
+-------------------------------------------------------------------------------
+[your text here]