Compiler executable 1

[SkymanOne]

Summary

Introduces a basic executable that can be used to init a new project and check for parser, semantic and type errors.

• folidity new <project_name> - initialise a new counter project in the destination directory.
• folidty check <file_name> - check the source code for parser, semantic and type errors.

We use ariadne and yansi for pretty display of errors.

There are also minor fixes to semantic analyser to correctly detect scopes:

• DeclarationBounds - contains variables that have been defined in declarations directly (e.g. fields, params, state bounds, attribute members
• FunctionBody - Body of the function
• ... - same as above.

If the original scope is DeclarationBounds then we can only access the variables in this scope context.
Otherwise, we can access variables that can only be defined in the function body + from state bound since this is the parameter injected into the function.

This PR also adds changelog.