Code cleanup (#133)

* gradle updateBuildScript

* fix comments and commented-out code

Code deletion, converting comments into javadocs, and refactoring code to not
need comments.

* remove redundant suppressions

* replace C-style array declaration with Java-style

* make private field final

* remove unnecessary semicolon

* extract a common part from an if

* simplify boolean expression

* simplify ternary if

* remove unused imports

* convert escaped characters for clarity

* replace while with for

* replace explicit types with diamond operators

* replace anonymous type with lambda

* enable modern Java syntax

* migrate to enhanced switch

* migrate to pattern variables for instanceof

* remove empty javadoc

* add Nonnull annotation to overrides of Nonnull methods

* replace wailaStack with null

When wailaStack is not null, the flow breaks out of the loop,
so there's no need to confuse the reader with putting wailaStack
both as the result and the parameter of the call - there's no
recursion.

* int cannot be bigger than its max value

* suppress dataflow warning

* remove redundant initializer

The default value of int is 0.

* null check is covered by instanceof

* simplify some calls of addVertexWithUV

* fix typos and add TODOs

* make flipState more understandable

src/main/java/com/glodblock/github/util/DualityFluidInterface.java

@@ -301,7 +301,7 @@ public class DualityFluidInterface implements IGridTickable, IStorageMonitorable
             toStore.setStackSize(-toStore.getStackSize());
             FluidStack canExtract = this.tanks.drain(slot, toStore.getFluidStack(), false);
             if (canExtract != null && (long) canExtract.amount == toStore.getStackSize()) {
-                IAEFluidStack notStored = dest.injectItems(toStore, Actionable.MODULATE, this.mySource);;
+                IAEFluidStack notStored = dest.injectItems(toStore, Actionable.MODULATE, this.mySource);
                 toStore.setStackSize(toStore.getStackSize() - (notStored == null ? 0L : notStored.getStackSize()));
                 if (toStore.getStackSize() > 0L) {
                     changed = true;