Follow up to https://github.com/aspnet/Docs/pull/7540
I found one more reference to versionless packages. I've updated the migration guide to remove this recommendation, and also briefly mentioned the most common issues users have encountered so far.
* WIP Migrate from 2.0 to 2.1
* work
* work
* work
* work
* work
* work
* work
* react to feedback
* react to feedback
* .
* Update 20_21.md
* Update 20_21.md
* Add a short migration doc page explaining how to migrate `ClaimsPrincipal.Current` usage
* Update file names to work with xref cross-references
* UE edit
* intiial commit for membership to Core Identity
* Update membership-to-core-identity.md
* fix sql script
* updates for Barry
* Style guide changes
* udpates to Migration Index Node and MVC Walkthrough
* updates to configuration and sample
* fixes to MVC steps
* udpates to proper to core identity doc and sample
* image resizing
* updates to webapi
* update to error section
* Minor tweaks to mvc.md
* Change snippet type
* remove references to bower in samples/readmes
* udpates for Scott
* updates to TOC
* updates
* Minor tweaks to membership-to-core-identity.md
* updates
* fix namespace
* Minor verbiage tweaks
* Simplify link title in TOC
* Shorten link title again
* Fix indentation of PackageReference node
* Quick UE edit
* Minor tweaks to configuration.md
* Remove unnecessary screenshots
* remove files
* Remove extra word
* Verbiage tweak
* Fix broken link
* Minor tweaks to mvc.md
* Improve readability of _Layout.cshtml
* Minor tweaks to mvc.md
* remove extra space
* Fix indentation issues
* Include file for ASP.NET Core 2.1 (#5702)
* Create 2.1.md
* Update 2.1.md
* Title, description, and H1 updates (3) (#5717)
* Refactor stdout logging warning (#5724)
* Add link to App Service troubleshooting topic (#5722)
* Prereqs tuneup (#5721)
Updates
* Updated http-cookies.md (#5744)
fixed inclues => includes
* changed image to vertical orientation for readability (#5747)
* Get CDN content links on HTTPS protocol (#5736)
* Update cookie sharing topic (#5723)
* Fixed type (#5748)
* Update highlight on dependency-injection.md (#5749)
Currently the highlight is mapping the operation of GetAveragePriority on the incorrect line:
[Statistics_Service.png](https://postimg.org/image/5m0gjw6bf/)
The correction is to highlight the previous line.
* Web API persistent DB (#5741)
* Update next.md
* Minor edits
* Replace gerund in doc title
* Update TodoController2.cs (#5755)
* Describe culture fallback (#5756)
* Describe culture fallback
* Culture fallback patch (#5757)