Add methods for incrementing normal version

pom.xml

@@ -4,7 +4,7 @@
 
   <groupId>com.github.zafarkhaja</groupId>
   <artifactId>semver</artifactId>
-  <version>0.2.1-SNAPSHOT</version>
+  <version>0.3.0-SNAPSHOT</version>
   <packaging>jar</packaging>
 
   <name>semver</name>

src/main/java/com/github/zafarkhaja/semver/Version.java

@@ -95,6 +95,18 @@ public class Version implements Comparable<Version> {
         return new Version(normal, preRelease, build);
     }
 
+    public void incrementMajorVersion() {
+        normal.incrementMajor();
+    }
+
+    public void incrementMinorVersion() {
+        normal.incrementMinor();
+    }
+
+    public void incrementPatchVersion() {
+        normal.incrementPatch();
+    }
+
     public int getMajorVersion() {
         return normal.getMajor();
     }

src/test/java/com/github/zafarkhaja/semver/VersionTest.java

@@ -150,6 +150,27 @@ public class VersionTest {
             assertEquals("rc.1", v.getPreReleaseVersion());
             assertEquals("build.1", v.getBuildVersion());
         }
+
+        @Test
+        public void shouldProvideIncrementMajorVersionMethod() {
+            Version v = Version.valueOf("1.2.3");
+            v.incrementMajorVersion();
+            assertEquals("2.0.0", v.toString());
+        }
+
+        @Test
+        public void shouldProvideIncrementMinorVersionMethod() {
+            Version v = Version.valueOf("1.2.3");
+            v.incrementMinorVersion();
+            assertEquals("1.3.0", v.toString());
+        }
+
+        @Test
+        public void shouldProvideIncrementPatchVersionMethod() {
+            Version v = Version.valueOf("1.2.3");
+            v.incrementPatchVersion();
+            assertEquals("1.2.4", v.toString());
+        }
     }
 
     public static class EqualsMethodTest {