Parsing unreachable code

[KrosFire]

Current amber compiler doesn't parse the code that is not being used. While it's a good practice performence wise, it's not that good when it comes to enforcing that amber files have correct syntax. This can lead to many bugs and maybe exploits. I think we need to address that as soon as possible.

The simplest idea is to introduce parsing as a separate phase. It would take a lot of work, but in the end code and compile process would be clearer.

Example of the issue:

fun foo(a: Num) {
    absolute giberish
    no real syntax at all
}

main {
    echo "some msg"
}

[Ph0enixKM]

A fix to this would require a full compiler overhaul. I think that once well planned - this could come out without any conflicts