[#252] Simple DAP executable

Description

Problem: we decided to use Debugger Adapter Protocol for morley-debugger UI, therefore we need its implementation.

Solution: add morley-debug-adapter executable that is able to parse VSCode's DAP messages and log them to file. Also add morley-debugger-vscode extension that is able to launch morley-debug-adapter from vscode.

Related issue(s)

Resolves #252 (closed).

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