Fix mingw compilation support

Support additional screen layouts.

And other minor style changes

Fix Travis build issue on mac

Minor Menu Fixes

Also minor style changes

Make small screen stay at 1x, and large screen maintain its aspect ratio.

Allows users to choose a single screen layout or a large screen layout.
Adds a configuration option to change the prominent screen.

AC_U: Stub functions, used if EULA agreed

Update Donation Info in Readme

Link main site donation page in readme instead of providing further donation info there.

NWM: stub Initialize with an error

Update CONTRIBUTING.md

Fix build on DragonFly and FreeBSD

Small fix to let IDA see target.xml

Citra SDL2 doesn't have a launcher, and citra.desktop tries to execute
citra-qt which is N/A unless built with ENABLE_QT. Limiting installed
files to one of the options also makes it easier to split them into
separate non-conflicting packages downstream.

/usr/bin/ld: ../common/libcommon.a(string_util.cpp.o): undefined reference to symbol 'libiconv_open'

In file included from src/common/microprofile.cpp:7:
In file included from src/./common/microprofile.h:23:
externals/microprofile/microprofile.h:830:5: error: use of undeclared identifier 'MP_BREAK'
    MP_ASSERT(t == nBegin);
    ^
externals/microprofile/microprofile.h:238:34: note: expanded from macro 'MP_ASSERT'
                                 ^
externals/microprofile/microprofile.h:831:5: error: use of undeclared identifier 'MP_BREAK'
    MP_ASSERT(nTimerIndex == (nToken&0x3fff));
    ^
externals/microprofile/microprofile.h:238:34: note: expanded from macro 'MP_ASSERT'
                                 ^
[...]

src/core/hle/service/soc_u.cpp:107:6: error: 'ENODATA' was not declared in this scope
     {ENODATA, 43},
      ^
src/core/hle/service/soc_u.cpp:117:6: error: 'ENOSR' was not declared in this scope
     {ENOSR, 53},
      ^
src/core/hle/service/soc_u.cpp:118:6: error: 'ENOSTR' was not declared in this scope
     {ENOSTR, 54},
      ^
src/core/hle/service/soc_u.cpp:139:6: error: 'ETIME' was not declared in this scope
     {ETIME, 75},
      ^

In file included from src/common/x64/cpu_detect.cpp:16:
/usr/include/machine/cpufunc.h:66:17: error: unknown type name 'u_int'
static __inline u_int
                ^
/usr/include/machine/cpufunc.h:67:6: error: unknown type name 'u_int'
bsfl(u_int mask)
     ^
/usr/include/machine/cpufunc.h:69:2: error: unknown type name 'u_int'
        u_int   result;
        ^
/usr/include/machine/cpufunc.h:75:17: error: unknown type name 'u_long'; did you mean 'long'?
static __inline u_long
                ^
/usr/include/machine/cpufunc.h:76:6: error: unknown type name 'u_long'; did you mean 'long'?
bsfq(u_long mask)
     ^
/usr/include/machine/cpufunc.h:78:2: error: use of undeclared identifier 'u_long'; did you mean
      'long'?
        u_long  result;
        ^
[...]

Most modern Unix environments use 64-bit off_t by default: OpenBSD,
FreeBSD, OS X, and Linux libc implementations such as Musl.

glibc is the lone exception; it can default to 32 bits but this is
configurable by setting _FILE_OFFSET_BITS.

Avoiding the stat64()/fstat64() interfaces is desirable because they
are nonstandard and not implemented on many systems (including
OpenBSD and FreeBSD), and using 64 bits for stat()/fstat() is either
the default or trivial to set up.