Add missing CallmeRequest class definitions

[piomin]

There are two empty CallmeRequest.kt files that need to be implemented:

1. inter-communication/inter-callme-service/src/main/kotlin/pl/piomin/samples/callme/model/CallmeRequest.kt
2. inter-communication/inter-caller-service/src/main/kotlin/pl/piomin/samples/caller/model/CallmeRequest.kt

These files should contain the CallmeRequest data class definition with id and message properties, which are referenced in other files.

/sweep