correct a typo in the install part of manual (file separator)

File separator in Windows is backslash instead of slash

Related to https://bz.apache.org/bugzilla/show_bug.cgi?id=64733

The main "writer" thread which initiates the writes to the PipedOutputStream (via the switched System.out/System.err) would exit/complete but would leave the SysOutErrStreamReader thread alive thus causing the PipedInputStream.read()s to continue happening in that SysOutErrStreamReader thread. This would cause the following IOException because the writer thread has exited and is no longer alive:

[junitlauncher] Caused by: java.io.IOException: Pipe broken
[junitlauncher] 	at java.base/java.io.PipedInputStream.read(PipedInputStream.java:321)
[junitlauncher] 	at java.base/java.io.PipedInputStream.read(PipedInputStream.java:377)
[junitlauncher] 	at java.base/java.io.InputStream.read(InputStream.java:205)
[junitlauncher] 	at org.apache.tools.ant.taskdefs.optional.junitlauncher.LauncherSupport$SysOutErrStreamReader.run(LauncherSupport.java:525)
[junitlauncher] 	... 1 more

Override ZipOutputStream.write(int)

Some tests were lost in migration to JUnit 4

Bugzilla Report 65105

Closes #125 pull request at github/apache/ant repo

also avoid double-encoding of sysout/err

Bugzilla Reports 63436 and 65030

#64855 Add filterbeforeconcat option to Concat

#64854 Add preserveduplicates option to ResourceList

* Ant 1.10 requires jdk 8 doc update

* Updated the manual to reflect ant requires JDK 8 +

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Merge tag 'rel/1.10.9'

Tagging version 1.10.9 of Ant

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While reviewing changeset 1.10.8 -> head