update docstrings and link to documentation

Author: egabancho

charts/invenio/values.yaml

@@ -86,6 +86,9 @@ invenio:
     ##
     secretKeys:
       dsnKey: "SENTRY_DSN"
+
+  ## Invenio DataCite configuration
+  ## ref: https://inveniordm.docs.cern.ch/customize/dois
   datacite:
     ## @param invenio.datacite.enabled Enable DataCite provider
     ##
@@ -96,7 +99,7 @@ invenio:
     ## @param invenio.datacite.password Datacite password
     ##
     password: ""
-    ## @param invenio.datacite.existingSecret Existing secret name for datacite username and password
+    ## @param invenio.datacite.existingSecret Existing secret name for datacite username and password.
     ##
     existingSecret: ""
     ## @param invenio.datacite.secretKeys.usernameKey Name of key in existing secret to use for username. Only used when `invenio.datacite.existingSecret` is set.
@@ -105,19 +108,19 @@ invenio:
     secretKeys:
       usernameKey: "DATACITE_USERNAME"
       passwordKey: "DATACITE_PASSWORD"
-    ## @param invenio.datacite.prefix DataCite DOI prefix
+    ## @param invenio.datacite.prefix DataCite DOI prefix, it will translate into DATACITE_PREFIX.
     ##
     prefix: ""
-    ## @param invenio.datacite.testMode DataCite test mode enabled.
+    ## @param invenio.datacite.testMode DataCite test mode enabled, it will trasnlate into DATACITE_TEST_MODE.
     ## This has to be a string value, Invenio will evaluate this as a python expression and transform it into a boolean.
     ## Example:
     ## testMode: "False"
     ##
     testMode: ""
-    ## @param invenio.datacite.format A string used for formatting the DOI.
+    ## @param invenio.datacite.format A string used for formatting the DOI, it will translate into DATACITE_FORMAT.
     ##
     format: ""
-    ## @param invenio.datacite.dataCenterSymbol DataCite data center symbol.
+    ## @param invenio.datacite.dataCenterSymbol DataCite data center symbol, it will translate into DATACITE_DATACENTER_SYMBOL.
     ##
     dataCenterSymbol: ""
     ## @param invenio.datacite.existing_secret DEPRECATED: use invenio.datacite.existingSecret instead