MASM test runner

[hackaugusto]

Idea

Add support to doctest for MASM code

Rationale

Increase test coverage, by making stupidly easy to write unit tests

Proposal

I would imitate the doctests from languages like rust/python, something like:

#! Validates that a non fungible asset is well formed. Panics if the asset is not well formed.
#!
#! ```test
#! push.0.0.0.0 exec.validate_non_fungible_asset
#! > FailedAssertion { err_code: 131128 }
#! ```
#!
#! Stack: [ASSET]
#! Outputs: [ASSET]
#!
#! ASSET is the asset to validate.
export.validate_non_fungible_asset
    # assert that ASSET[1] is a valid account id
    dup.2 exec.account::validate_id
    # => [ASSET]

    # assert that ASSET[1] is a fungible faucet
    dup.2 exec.account::is_non_fungible_faucet assert.err=ERR_NON_FUNGIBLE_ASSET_FORMAT_POSITION_ONE_MUST_FUNGIBLE
    # => [ASSET]

    # assert the fungible bit is set to 0
    dup u32split swap drop
    push.FUNGIBLE_BITMASK_U32 u32and assertz.err=ERR_NON_FUNGIBLE_ASSET_HIGH_BIT_SET
    # => [ASSET]
end

Another approach is to add test.<name> ... end.

Test execution would be as simple as parsing the code and calling a method in the module to collect/run the tests.

[hackaugusto]

The approach above is intentionally simple. There tons of things that could be done around testing. And IMO anything fancier should be discussed as another issue. Here I'm trying to propose the minimum that would quickly improve productivity when testing.