adda note about ARM in the readme

closes sqlpage#382

README.md

@@ -180,6 +180,9 @@ To run on a server, you can use [the docker image](https://hub.docker.com/r/lova
     COPY --from=lovasoa/sqlpage:main /usr/local/bin/sqlpage /usr/local/bin/sqlpage
     ``` 
 
+We provide compiled binaries only for the x86_64 architecture, but provide docker images for other architectures, including arm64 and armv7. If you want to run SQLPage on a Raspberry Pi or 
+a cheaper ARM cloud instance, using the docker image is the easiest way to do it.
+
 ### On Mac OS, with homebrew
 
 An alternative for Mac OS users is to use [SQLPage's homebrew package](https://formulae.brew.sh/formula/sqlpage).