started implementing poll backend

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

backend/build.gradle.kts

@@ -23,6 +23,7 @@ dependencies{
     implementation(project(":markdown"))
     implementation(project(":messages"))
     implementation(project(":notes"))
+    implementation(project(":poll"))
     implementation(project(":project"))
     implementation(project(":stock"))
     implementation(project(":tags"))