Support all the array types

Author: sakthivelmanii

src/main/java/com/google/cloud/spanner/jdbc/JdbcDataType.java

@@ -163,6 +163,7 @@ public Type getSpannerType() {
   },
   FLOAT64 {
     private final Set<Class<?>> classes = new HashSet<>(Arrays.asList(Float.class, Double.class));
+    private final Set<String> aliases = new HashSet<>(Collections.singletonList("float8"));
 
     @Override
     public int getSqlType() {
@@ -193,6 +194,11 @@ public List<Double> getArrayElements(ResultSet rs, int columnIndex) {
     public Type getSpannerType() {
       return Type.float64();
     }
+
+    @Override
+    public Set<String> getAliases() {
+      return aliases;
+    }
   },
   INT64 {
     private final Set<Class<?>> classes =