New feature: shareable user query (#6052)

* New feature: shareable user query
Share the output of a user query by RSS / HTML / OPML with other people through unique URLs.
Replaces the global admin token, which was the only option (but unsafe) to share RSS outputs with other people.
Also add a new HTML output for people without an RSS reader.

fix https://github.com/FreshRSS/FreshRSS/issues/3066#issuecomment-648977890
fix https://github.com/FreshRSS/FreshRSS/issues/3178#issuecomment-769435504

* Remove unused method

* Fix token saving

* Implement HTML view

* Update i18n for master token

* Revert i18n get_favorite

* Fix missing i18n for user queries from before this PR

* Remove irrelevant tests

* Add link to RSS version

* Fix getGet

* Fix getState

* Fix getSearch

* Alternative getSearch

* Default getOrder

* Explicit default state

* Fix test

* Add OPML sharing

* Remove many redundant SQL queries from original implementation of user queries

* Fix article tags

* Use default user settings

* Prepare public search

* Fixes

* Allow user search on article tags

* Implement user search

* Revert filter bug

* Revert wrong SQL left outer join change

* Implement checkboxes

* Safe check of OPML

* Fix label

* Remove RSS button to favour new sharing method
That sharing button was using a global admin token

* First version of HTTP 304

* Disallow some recusrivity
fix https://github.com/FreshRSS/FreshRSS/issues/6086

* Draft of nav

* Minor httpConditional

* Add support for offset for pagination

* Fix offset pagination

* Fix explicit order ASC

* Add documentation

* Help links i18n

* Note about deprecated master token

* Typo

* Doc about format

1 files changed, 5 insertions, 1 deletions

diff --git a/README.md b/README.md
index 4f2629975..953e858b0 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,11 @@ There is an API for (mobile) clients, and a [Command-Line Interface](cli/README.
 Thanks to the [WebSub](https://freshrss.github.io/FreshRSS/en/users/WebSub.html) standard,
 FreshRSS is able to receive instant push notifications from compatible sources, such as [Friendica](https://friendi.ca), [WordPress](https://wordpress.org/plugins/pubsubhubbub/), Blogger, Medium, etc.
 
-FreshRSS natively supports basic Web scraping, based on [XPath](https://www.w3.org/TR/xpath-10/), for Web sites not providing any RSS / Atom feed.
+FreshRSS natively supports basic [Web scraping](https://freshrss.github.io/FreshRSS/en/users/11_website_scraping.html),
+based on [XPath](https://www.w3.org/TR/xpath-10/), for Web sites not providing any RSS / Atom feed.
+Also supports JSON documents.
+
+FreshRSS offers the ability to [reshare selections of articles by HTML, RSS, and OPML](https://freshrss.github.io/FreshRSS/en/users/user_queries.html).
 
 Different [login methods](https://freshrss.github.io/FreshRSS/en/admins/09_AccessControl.html) are supported: Web form (including an anonymous option), HTTP Authentication (compatible with proxy delegation), OpenID Connect.