Release Name: 0.2.0

Notes:
This update contains a few important core emulation fixes,
and adds support for joysticks and zip-compressed files.

It also contains some general bug-fixes and corrections all
over the map.

Thanks to everyone who´s either contributed code or
notified me of problems. See the changelog for more
details.

Changes:
libgambatte:
- fix 64-bit compile and segfault. Thanks to Nach for noticing.
- Add zip support. Thanks to Nach for contributing nice, clear code
- fix sound ch4 frequency calculation
- Several PPU reads timings depend on wx. Thanks to franpa for noticing the
corrupt line in The LoZ: Oracle of Seasons.
- remove unused doubleSpeed parameter from m3ExtraCycles call
gambatte_sdl:
- Thread safety, bigger sound buffer
- Compile on more platforms. Thanks to Thristian for the find.
- actually increment iterator so the loop makes some sense (parser.cpp)
gambatte_qt:
- fix 64-bit compile. Thanks to Nach.
- better license info for x11getprocaddress.cpp
- initial joystick support, mostly using SDL´s joystick code (separated from
the rest of SDL)
- use binary search for gb inputs.
all:
- make sure to use std:: despite sloppy compilers allowing omission. Thanks
to blargg for the reminder.
- get rid of some valgrind warnings. Thanks to Nach for noticing.
hwtests:
- add tests for wx effects on PPU read timings.
build:
- add -Wextra to default compile flags
doc:
- mention optional zlib dependency
- additions to thanks section