Improve Light Queue and force enable it for all

There is no reason for the light queue to even be an option. This
enables the light queue for everyone.

This also improves the "can we still tick" time logic to always
check before running a light operation.

previously, we always executed at least 10 on the first world
(but not other worlds...), but we are seeing light take up some
heavy time, so improving that for now.

I've now also improved recheck gaps logic to happen at the end of all single block updates

This also prevents multiple gap checks, as previously if a tick skipped
the gaps check, the next tick would end up re-adding the entry again,
resulting in multiple gap checks.

This now just sets a marker "We need to recheck gaps" and will only occur
once.

This also should reduce chunk loads, as previously, we checked if
the neighbor chunks were loaded for the gap check, however those
neighbor chunks might of unloaded before the light queue operation
actually ran. Now, the neighbor chunk is done when the gap check
is being done, so it should avoid loading chunks.

Fixes #1466
Fixes #1431

Spigot-Server-Patches/Configurable-end-credits.patch

@@ -5,12 +5,12 @@ Subject: [PATCH] Configurable end credits
 
 
 diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
-index 4b36a0f053..53921b381e 100644
+index 9fd1bde0ef..29d5f30545 100644
 --- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
 +++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
 @@ -0,0 +0,0 @@ public class PaperWorldConfig {
-         queueLightUpdates = getBoolean("queue-light-updates", false);
-         log("Lighting Queue enabled: " + queueLightUpdates);
+         //queueLightUpdates = getBoolean("queue-light-updates", false);
+         //log("Lighting Queue enabled: " + queueLightUpdates);
      }
 +
 +    public boolean disableEndCredits;
@@ -20,7 +20,7 @@ index 4b36a0f053..53921b381e 100644
 +    }
  }
 diff --git a/src/main/java/net/minecraft/server/EntityPlayer.java b/src/main/java/net/minecraft/server/EntityPlayer.java
-index 3112ee5453..9f23c0d2c2 100644
+index 09e2859c4a..95ab3d2cda 100644
 --- a/src/main/java/net/minecraft/server/EntityPlayer.java
 +++ b/src/main/java/net/minecraft/server/EntityPlayer.java
 @@ -0,0 +0,0 @@ public class EntityPlayer extends EntityHuman implements ICrafting {