Switch to Java 1.8

Travis CI now support Java 1.8 early access so switch to that directly
so that we can use new Java programming language features and reuse the
JVM functional interfaces for code generation.

Signed-off-by: Pekka Enberg <penberg@kernel.org>

.travis.yml

@@ -1,4 +1,3 @@
 language: java
 jdk:
-  - openjdk7
-  - oraclejdk7
+  - oraclejdk8

README.md

@@ -13,7 +13,7 @@ hacking on F# implementation for the JVM, welcome on board!
 ### Requirements
 
 Fjord is built and packaged with [Apache Maven][Apache Maven] and requires Java
-1.7 or higher to build and run.
+1.8 or higher to build and run.
 
 ### Building from sources
 

pom.xml

@@ -67,8 +67,8 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <version>2.3.2</version>
         <configuration>
-          <source>1.7</source>
-          <target>1.7</target>
+          <source>1.8</source>
+          <target>1.8</target>
           <encoding>${project.build.sourceEncoding}</encoding>
         </configuration>
       </plugin>