Fix int overflow occurred in mojiFIle.getInputStream()

Fix the exception below:

    Exception in thread "main" java.lang.ArithmeticException: The byte count 5368709120 is too large to be converted to an int
        at org.apache.commons.io.input.CountingInputStream.getCount(CountingInputStream.java:91)
        at fm.last.moji.impl.FileDownloadInputStream.close(FileDownloadInputStream.java:65)
        at net.hicloud.s3.testMogileInputStream.TestMogileStorageInputStream.main(TestMogileStorageInputStream.java:70)