Add Japanese manual

[gerundt]

This PR adds the Japanese manual from @sdottaka to the official WinMerge. I also tweaked the folder structure from the manual to support different languages of the manuals:

• Docs\Manual
  • EN English manual
  • JP Japanese manual
  • Tools Place for the build tools

The only problem is, that I get encoding problems because my Windows has no Shift_JIS installed. Maybe it is possible to switch to UTF-8?

[sdottaka]

Thank you!

The only problem is, that I get encoding problems because my Windows has no Shift_JIS installed. Maybe it is possible to switch to UTF-8?

I'll look at it later.

[sdottaka]

Unfortunately, "The HTML Help Compiler is not UTF-8 aware" (http://docbook.sourceforge.net/release/xsl/current/doc/html/htmlhelp.encoding.html).
For this reason, I changed to use xsltproc which can use Shift_JIS instead of Saxon as XSLT processor.