[#266] Docker image with morley-debugger

Description

Problem: We want to have a nice way to distribute our debugger. Building project from scratch doesn't sound like a good idea.

Solution: Add a way to build docker image with morley-debugger. Such an approach is a bit better than producing static binaries. At first, docker can easily upgrade images without reuploading manually. Second, it more cross-platform.

Apart from new image in the registry, new morley-debugger.sh script wrapper was added.

Related issue(s)

Resolves part of #266 (closed) (we decided that proper morley-client distribution isn't urgent and can be done later)

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