Revert "Updated liquibase dependency to 3.2."

This reverts commit d6621e62ad. I think
the test failure might be a bug in Liquibase:
https://liquibase.jira.com/browse/CORE-2094

spring-boot-dependencies/pom.xml

@@ -91,7 +91,7 @@
 		<json-path.version>0.9.1</json-path.version>
 		<jstl.version>1.2</jstl.version>
 		<junit.version>4.11</junit.version>
-		<liquibase.version>3.2.2</liquibase.version>
+		<liquibase.version>3.0.8</liquibase.version>
 		<log4j.version>1.2.17</log4j.version>
 		<log4j2.version>2.0.2</log4j2.version>
 		<logback.version>1.1.2</logback.version>

spring-boot/src/main/java/org/springframework/boot/liquibase/SpringPackageScanClassResolver.java

@@ -47,20 +47,25 @@ public class SpringPackageScanClassResolver extends DefaultPackageScanClassResol
 		this.logger = logger;
 	}
 
-    @Override
-    protected void findAllClasses(String packageName, ClassLoader loader) {
-        MetadataReaderFactory metadataReaderFactory = new CachingMetadataReaderFactory(
-                loader);
-        try {
-            Resource[] resources = scan(loader, packageName);
-            for (Resource resource : resources) {
-                addFoundClass(loadClass(loader, metadataReaderFactory, resource));
-            }
-        }
-        catch (IOException ex) {
-            throw new IllegalStateException(ex);
-        }
-    }
+	@Override
+	protected void find(PackageScanFilter test, String packageName, ClassLoader loader,
+			Set<Class<?>> classes) {
+		MetadataReaderFactory metadataReaderFactory = new CachingMetadataReaderFactory(
+				loader);
+		try {
+			Resource[] resources = scan(loader, packageName);
+			for (Resource resource : resources) {
+				Class<?> candidate = loadClass(loader, metadataReaderFactory, resource);
+				if (candidate != null && test.matches(candidate)) {
+					classes.add(candidate);
+				}
+			}
+		}
+		catch (IOException ex) {
+			throw new IllegalStateException(ex);
+		}
+	}
+
 	private Resource[] scan(ClassLoader loader, String packageName) throws IOException {
 		ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver(loader);
 		String pattern = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX