chore(apps): move icons into the apps folder (#3139)

* chore(apps): move icons into the apps folder

* rename to `icon.png`

* replace solr image

* remove `docs/` from gitignore

* move app specific docs into app folder [skip ci]

* fix some links

* chore(apps): update image links temporary

charts/stable/spotweb/docs/validation.md

@@ -0,0 +1,42 @@
+# Input Validation
+
+## Admin Username
+
+Usernames for an administrator in spotweb have some restrictions.
+
+* Following words are not allowed:
+  * god
+  * mod
+  * spot
+  * admin
+  * drazix
+  * superuser
+  * supervisor
+  * root
+  * anonymous
+* Following characters are not allowed:
+  * <
+  * \>
+* Regex used to validate the username (you can try live [here](https://regex101.com/r/LA4Io7/1)):
+ `^((?!god|mod|spot|admin|drazix|superuser|supervisor|root|anonymous)[^<>])*$`
+
+## Admin Firstname and Lastname
+
+The firstname and lastname  in spotweb have some restrictions.
+
+* Following characters are not allowed:
+  * <
+  * \>
+* Minimum lenght of 2 characters is enforced
+* Regex used to validate the firstname and lastname (you can try live [here](https://regex101.com/r/x2KGnU/1)):
+ `^([^<>]{2})([^<>]*)$`
+
+## Admin Email
+
+The email addres is validated in spotweb using the built-in `_FILTER_VALIDATE_EMAIL`.
+
+* Regex used to validate the email (you can try live [here](https://regex101.com/r/yEmCoL/1)):
+ ```^[a-zA-Z0-9.!#$%&'*+\/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$```
+
+---
+If you find a field that you think it needs validation, please open an issue on github