Add references to Nbshell in export templates, reports and scripts

[8ctorres]

Fixes: #15014

The Netbox shell is a very powerful resource for people trying to develop their own scripts, reports or configuration templates, but I feel it is difficult to find in the documentation. For this reason, I have added a few references to it in the pages, so that a new user can find it much sooner than it took me to find.

[jeremystretch]

Thanks @8ctorres. Let's compress some of the commentary on using nbshell to ensure we don't disrupt from the primary flow of each page.

[8ctorres]

Hi @jeremystretch thanks for your feedback. I will try to make some changes this weekend and update the PR.

[jeremystretch]

@8ctorres checking in. Are you still working on this PR?

[8ctorres]

Hi @jeremystretch thanks for checking. I haven't really had the time these past few weeks, I apologize for the delay. I will try to get this done before the end of the month. Sorry again

[8ctorres]

Hi @jeremystretch , sorry again for the delay with this. I have reviewed your suggestions and added another commit with a few changes. About reports, I see that they're being deprecated in v4, so maybe the documentation on that section isn't going to be so relevant anymore.

Thanks!