Feature Request: ability to add prepend/append code

[nxuv]

I.e for running C or C++ or D code i'd have to prepend and append some code before running it

For C it'd be something like

#include <stdio.h>

int main() {
    // SELECTED CODE GOES HERE
    return 0;
}

For C++ it'd be something like

#include <iostream>

int main() {
    // SELECTED CODE GOES HERE
    return 0;
}

For D it'd be something like

/+ dub.sdl:
name "test"
+/

import std;

void main() {
    // SELECTED CODE GOES HERE
}

So possibly allow in file_types to have definition of something like file_template, i.e

opts = {
    file_types = {
        d = {
            cmd = "dub run --single",
            file_template = '/+ dub.sdl:\nname "test"\n+/\nimport std;\nvoid main() {\n${CODE}\n}\n'
        }
    }
}

[nxuv]

Ok, still related to #33 imagine this scenario. I'm selecting entire file and make it run. If to implement this feature then there would be big collision and shadowing. I.e

/+ dub.sdl:
name "test"
+/

import std;

void main() {
    // QuickCodeRunner injected code start
/+ dub.sdl:
name "test"
+/

import std;
import core.thread;

void main() {
    writeln("Hello");
    Thread.sleep(2000);
    writeln("After wait");
}
    // QuickCodeRunner injected code end
}

Not the ideal scenario, so this would also require something to allow code to be executed without templates, like a command :QuickCodeRunnerAsIs or something similar