Fix for unit tests run with ant 1.9

If the test suite is run with ant 1.9 (tested with 1.9.3), the following error occurs:

    [...]
    jar:
    
    copy-test-source:
        [mkdir] Created dir: /home/simleo/git/bioformats/components/bio-formats-plugins/build/test/classes
         [copy] Copied 3 empty directories to 3 empty directories under /home/simleo/git/bioformats/components/bio-formats-plugins/build/test/classes
    
    compile-tests:
        [javac] Compiling 3 source files to /home/simleo/git/bioformats/components/bio-formats-plugins/build/test/classes
    
    test:
        [junit] Testsuite: loci.plugins.in.AutoscaleTest
        [junit] Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0 sec
        [junit] 
        [junit] ------------- Standard Error -----------------
        [junit] SLF4J: Class path contains multiple SLF4J bindings.
        [junit] SLF4J: Found binding in [jar:file:/home/simleo/git/bioformats/artifacts/logback-classic-1.1.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
        [junit] SLF4J: Found binding in [jar:file:/home/simleo/git/bioformats/jar/logback-classic-1.1.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
        [junit] SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
        [junit] SLF4J: Actual binding is of type [ch.qos.logback.classic.util.ContextSelectorStaticBinder]
        [junit] ------------- ---------------- ---------------
        [junit] Null Test: 	Caused an ERROR
        [junit] junit/framework/JUnit4TestAdapterCache
        [junit] java.lang.NoClassDefFoundError: junit/framework/JUnit4TestAdapterCache
        [junit] 	at java.lang.ClassLoader.defineClass1(Native Method)
        [junit] 	at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631)
        [junit] 	at java.lang.ClassLoader.defineClass(ClassLoader.java:615)
        [junit] 	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
        [junit] 	at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
        [junit] 	at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
        [junit] 	at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
        [junit] 	at java.security.AccessController.doPrivileged(Native Method)
        [junit] 	at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        [junit] 	at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        [junit] 	at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
        [junit] 	at java.lang.Class.forName0(Native Method)
        [junit] 	at java.lang.Class.forName(Class.java:169)
        [junit] 	at net.sf.antcontrib.logic.IfTask.execute(IfTask.java:197)
        [junit] 	at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        [junit] 	at java.security.AccessController.doPrivileged(Native Method)
        [junit] 	at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        [junit] 	at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        [junit] 	at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
        [junit] 
        [junit] 

This PR introduces a fix described [here](https://github.com/real-logic/simple-binary-encoding/issues/96)