qrencode: update to 4.0.2

Version 4.0.2 (2018.6.6)
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* Build script fixes. (Thanks to @mgorny)

Version 4.0.1 (2018.6.4)
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* CMake support improved.
* New test scripts have been added.
* Some compile time warnings have been fixed.

Version 4.0.0 (2017.9.21)
-------------------------
* Memory efficiency has been improved.
* QRcode_clearCache() has been deprecated.
* Error correction code generating functions have been improved.
* Command line tool "qrencode" has been improved:
	* XPM support. (Thanks to Tobias Klauser)
	* PNG32 (direct color mode) support. (Thanks to Greg Hart)
	* EPS output now supports foreground and background color.
	* New options "-r" and "--svg-path" have been added.
	  (Thanks to Robert Petersen and @Oblomov)
* CMake support has been added. (optional) (Thanks to @misery)
* Various bug fixes.
* Various performance improvements.

Release Note:
While the API has not been changed since the previous major release, we
incremented the major version number of libqrencode to 4 because the
implementation of the library has been largely changed.

This release improves the performance and memory footprints of code generation.

Now you can build libqrencode with CMake.

If you build the test programs, please note that the required SDL version has
been changed from 1.2 to 2.0.


(tnn)