specify utf8 encoding

this should fix the following known bugs:
 - putting a U+2019 in the config causes it to become corrupted and
   ~double in size every launch
 - scripts become assembled incorrectly and the nbsp after your name in
   the chatbox becomes incorrect
 - the feed panel doesn't show emoji

cache/src/main/java/net/runelite/cache/fs/flat/FlatStorage.java

@@ -33,6 +33,7 @@ import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.PrintStream;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Base64;
 import java.util.Comparator;
@@ -103,7 +104,7 @@ public class FlatStorage implements Storage
 		for (Index idx : store.getIndexes())
 		{
 			String file = idx.getId() + EXTENSION;
-			try (BufferedReader br = new BufferedReader(new InputStreamReader(openReader(file))))
+			try (BufferedReader br = new BufferedReader(new InputStreamReader(openReader(file), StandardCharsets.UTF_8)))
 			{
 				int lineNo = 0;
 				Archive archive = null;
@@ -213,7 +214,7 @@ public class FlatStorage implements Storage
 		for (Index idx : store.getIndexes())
 		{
 			String file = idx.getId() + EXTENSION;
-			try (PrintStream br = new PrintStream(openWriter(file)))
+			try (PrintStream br = new PrintStream(openWriter(file), false, StandardCharsets.UTF_8.name()))
 			{
 				br.printf("protocol=%d\n", idx.getProtocol());
 				br.printf("revision=%d\n", idx.getRevision());

cache/src/main/java/net/runelite/cache/io/OutputStream.java

@@ -26,8 +26,8 @@ package net.runelite.cache.io;
 
 import com.google.common.base.Preconditions;
 import java.io.IOException;
-import java.io.UnsupportedEncodingException;
 import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
 
 public final class OutputStream extends java.io.OutputStream
 {
@@ -181,16 +181,7 @@ public final class OutputStream extends java.io.OutputStream
 
 	public void writeString(String str)
 	{
-		byte[] b;
-		try
-		{
-			b = str.getBytes("ISO-8859-1");
-		}
-		catch (UnsupportedEncodingException ex)
-		{
-			throw new RuntimeException(ex);
-		}
-		writeBytes(b);
+		writeBytes(str.getBytes(StandardCharsets.ISO_8859_1));
 		writeByte(0);
 	}
 

cache/src/main/java/net/runelite/cache/script/assembler/Assembler.java

@@ -26,6 +26,8 @@ package net.runelite.cache.script.assembler;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
 import net.runelite.cache.definitions.ScriptDefinition;
 import net.runelite.cache.script.Instructions;
 import net.runelite.cache.script.assembler.rs2asmParser.ProgContext;
@@ -45,7 +47,7 @@ public class Assembler
 	public ScriptDefinition assemble(InputStream in) throws IOException
 	{
 		// Get our lexer
-		rs2asmLexer lexer = new rs2asmLexer(new ANTLRInputStream(in));
+		rs2asmLexer lexer = new rs2asmLexer(new ANTLRInputStream(new InputStreamReader(in, StandardCharsets.UTF_8)));
 
 		LexerErrorListener errorListener = new LexerErrorListener();
 		lexer.addErrorListener(errorListener);

cache/src/test/java/net/runelite/cache/script/assembler/AssemblerTest.java

@@ -25,6 +25,7 @@
 package net.runelite.cache.script.assembler;
 
 import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
 import net.runelite.cache.definitions.ScriptDefinition;
 import net.runelite.cache.script.Instructions;
 import net.runelite.cache.script.disassembler.Disassembler;
@@ -76,7 +77,7 @@ public class AssemblerTest
 		in = AssemblerTest.class.getResourceAsStream(this.script);
 		Assert.assertNotNull(in);
 
-		String original = new String(IOUtils.toByteArray(in)).replaceAll("\r\n", "\n");
+		String original = new String(IOUtils.toByteArray(in), StandardCharsets.UTF_8).replaceAll("\r\n", "\n");
 
 		logger.info(original);
 		logger.info("-----------------------");

cache/src/test/java/net/runelite/cache/script/disassembler/DisassemblerTest.java

@@ -27,6 +27,7 @@ package net.runelite.cache.script.disassembler;
 import com.google.common.io.Files;
 import java.io.File;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import net.runelite.cache.IndexType;
 import net.runelite.cache.StoreLocation;
 import net.runelite.cache.definitions.ScriptDefinition;
@@ -78,7 +79,7 @@ public class DisassemblerTest
 				Disassembler disassembler = new Disassembler();
 				String out = disassembler.disassemble(script);
 
-				Files.write(out.getBytes(), outFile);
+				Files.write(out.getBytes(StandardCharsets.UTF_8), outFile);
 
 				++count;
 			}

cache/src/test/java/net/runelite/cache/util/XteaTest.java

@@ -24,6 +24,7 @@
  */
 package net.runelite.cache.util;
 
+import java.nio.charset.StandardCharsets;
 import static org.junit.Assert.assertArrayEquals;
 import org.junit.Test;
 
@@ -32,7 +33,7 @@ public class XteaTest
 	@Test
 	public void test()
 	{
-		byte[] data = "testtesttest1".getBytes();
+		byte[] data = "testtesttest1".getBytes(StandardCharsets.UTF_8);
 
 		int[] key = new int[]
 		{