update README as plugin is available from marketplace

Author: Loggy

README.md

@@ -2,19 +2,16 @@
 
 ## Getting started
 
-1. Get the zip file from the Github [releases page](https://github.com/pyroscope-io/grafana-panel-plugin/tags) on panel plugin repo.
-2. Get the zip file from the Github [releases page](https://github.com/pyroscope-io/grafana-datasource-plugin/tags) on datasource plugin repo.
-3. Extract zip files into the plugins directory for Grafana.
-4. Restart Grafana
-5. Open Grafana ang go to **Configuratin -> Plugins**
-6. Check that plugins are available:
-   ![plugins-list](https://raw.githubusercontent.com/pyroscope-io/grafana-panel-plugin/main/docs/assets/pluginslist.jpg)
-7. Set up data source plugin:
+1. Install the plugin (Installation tab)
+2. Install [datasource plugin](https://grafana.com/grafana/plugins/pyroscope-datasource/)
+3. Open Grafana ang go to **Configuratin -> Plugins**
+4. Check that plugins are available
+5. Set up data source plugin:
    * **Configuration -> Data Sources -> Add data source**
    * click on `pyroscope-datasource`
    * Specify Pyroscope host in `Endpoint` field:
       ![endpoint](https://raw.githubusercontent.com/pyroscope-io/grafana-panel-plugin/main/docs/assets/endpoint.jpg)
-8. Set up panel plugin:
+6. Set up panel plugin:
     * Add an empty panel on your dashboard
     * Select `pyroscop-panel` from Visualization list
     * Under panel view in Query tab select `pyroscope-datasource`