Fix wrong friendly name for storage_power in solaredge (home-assistant#141269)

* Fix wrong friendly name for `storage_power` in `solaredge`

"Stored power" is a contradiction in itself.
You can only store energy.

* Two additional spelling fixes

* Sentence-case "site"

Author: NoRi2909

homeassistant/components/solaredge/strings.json

@@ -5,7 +5,7 @@
         "title": "Define the API parameters for this installation",
         "data": {
           "name": "The name of this installation",
-          "site_id": "The SolarEdge site-id",
+          "site_id": "The SolarEdge site ID",
           "api_key": "[%key:common::config_flow::data::api_key%]"
         }
       }
@@ -14,7 +14,7 @@
       "already_configured": "[%key:common::config_flow::abort::already_configured_device%]",
       "invalid_api_key": "[%key:common::config_flow::error::invalid_api_key%]",
       "site_not_active": "The site is not active",
-      "could_not_connect": "Could not connect to the solaredge API"
+      "could_not_connect": "Could not connect to the SolarEdge API"
     },
     "abort": {
       "already_configured": "[%key:common::config_flow::abort::already_configured_device%]"
@@ -65,7 +65,7 @@
         "name": "Grid power"
       },
       "storage_power": {
-        "name": "Stored power"
+        "name": "Storage power"
       },
       "purchased_energy": {
         "name": "Imported energy"