Add "Min API" setting

[EpicDima]

Changing min API can be useful when working with R8, when it changes the code for older APIs.

Example:

import java. lang. Thread
import android.os.Looper

fun test3() {
    Looper.getMainLooper().isCurrentThread()
}

DEX with min API 21 (R8 enabled):

class KotlinExplorerKt$$ExternalSyntheticApiModelOutline0
    void KotlinExplorerKt$$ExternalSyntheticApiModelOutline0.m(android.os.Looper)
        -- 2 instructions
        0000: invoke-virtual {v0}, Landroid/os/Looper;.isCurrentThread:()Z // method@0003
        0003: return-void

class KotlinExplorerKt
    void KotlinExplorerKt.test3()
        -- 4 instructions
        0000: invoke-static {}, Landroid/os/Looper;.getMainLooper:()Landroid/os/Looper; // method@0002
        0003: move-result-object v0
        0004: invoke-static {v0}, LKotlinExplorerKt$$ExternalSyntheticApiModelOutline0;.m:(Landroid/os/Looper;)V // method@0000
        0007: return-void

DEX with min API 26 (R8 enabled):

class KotlinExplorerKt
    void KotlinExplorerKt.test3()
        -- 4 instructions
        0000: invoke-static {}, Landroid/os/Looper;.getMainLooper:()Landroid/os/Looper; // method@0001
        0003: move-result-object v0
        0004: invoke-virtual {v0}, Landroid/os/Looper;.isCurrentThread:()Z // method@0002
        0007: return-void

[romainguy]

Thanks! This is something I've been meaning to add, glad you beat me to it :)