chore: add network chain id

src/main/java/org/arkecosystem/crypto/networks/Devnet.java

@@ -2,6 +2,10 @@
 
 public class Devnet implements INetwork {
 
+    public int chainId() {
+        return 11812;
+    }
+
     public int version() {
         return 30;
     }

src/main/java/org/arkecosystem/crypto/networks/INetwork.java

@@ -2,6 +2,8 @@
 
 public interface INetwork {
 
+    int chainId();
+
     int version();
 
     int wif();

src/main/java/org/arkecosystem/crypto/networks/Mainnet.java

@@ -2,6 +2,10 @@
 
 public class Mainnet implements INetwork {
 
+    public int chainId() {
+        return 11811;
+    }
+
     public int version() {
         return 23;
     }

src/main/java/org/arkecosystem/crypto/networks/Testnet.java

@@ -2,6 +2,10 @@
 
 public class Testnet implements INetwork {
 
+    public int chainId() {
+        return 11812;
+    }
+
     public int version() {
         return 23;
     }

src/test/java/org/arkecosystem/crypto/networks/DevnetTest.java

@@ -6,6 +6,11 @@
 
 class DevnetTest {
 
+    @Test
+    void chainId() {
+        assertEquals(11812, new Devnet().chainId());
+    }
+
     @Test
     void version() {
         assertEquals(0x1E, new Devnet().version());

src/test/java/org/arkecosystem/crypto/networks/MainnetTest.java

@@ -6,6 +6,11 @@
 
 class MainnetTest {
 
+    @Test
+    void chainId() {
+        assertEquals(11811, new Mainnet().chainId());
+    }
+
     @Test
     void version() {
         assertEquals(0x17, new Mainnet().version());

src/test/java/org/arkecosystem/crypto/networks/TestnetTest.java

@@ -6,6 +6,11 @@
 
 class TestnetTest {
 
+    @Test
+    void chainId() {
+        assertEquals(11812, new Testnet().chainId());
+    }
+
     @Test
     void version() {
         assertEquals(0x17, new Testnet().version());