Update documentation.

- Convert http to https, provide archive link when possible.
- Made CPU-JIT.png more readable on dark themes;
Added a white background so there isn't black text on a black
background.

src/xenia/cpu/ppc/ppc_emit_altivec.cc

@@ -31,7 +31,7 @@ Value* CalculateEA_0(PPCHIRBuilder& f, uint32_t ra, uint32_t rb);
 // Most of this file comes from:
 // http://biallas.net/doc/vmx128/vmx128.txt
 // https://github.com/kakaroto/ps3ida/blob/master/plugins/PPCAltivec/src/main.cpp
-// http://sannybuilder.com/forums/viewtopic.php?id=190
+// https://sannybuilder.com/forums/viewtopic.php?id=190
 
 #define OP(x) ((((uint32_t)(x)) & 0x3f) << 26)
 #define VX128(op, xop) (OP(op) | (((uint32_t)(xop)) & 0x3d0))
@@ -2068,7 +2068,7 @@ int InstrEmit_vpkd3d128(PPCHIRBuilder& f, const InstrData& i) {
       assert_unhandled_case(type);
       return 1;
   }
-  // http://hlssmod.net/he_code/public/pixelwriter.h
+  // https://hlssmod.net/he_code/public/pixelwriter.h
   // control = prev:0123 | new:4567
   uint32_t control = kIdentityPermuteMask;  // original
   switch (pack) {
@@ -2141,7 +2141,8 @@ int InstrEmit_vpkd3d128(PPCHIRBuilder& f, const InstrData& i) {
 
 int InstrEmit_vupkd3d128(PPCHIRBuilder& f, const InstrData& i) {
   // Can't find many docs on this. Best reference is
-  // http://worldcraft.googlecode.com/svn/trunk/src/qylib/math/xmmatrix.inl,
+  // https://code.google.com/archive/p/worldcraft/source/default/source?page=4
+  // (qylib/math/xmmatrix.inl)
   // which shows how it's used in some cases. Since it's all intrinsics,
   // finding it in code is pretty easy.
   const uint32_t vd = i.VX128_3.VD128l | (i.VX128_3.VD128h << 5);

src/xenia/cpu/ppc/ppc_emit_fpu.cc

@@ -26,7 +26,7 @@ using xe::cpu::hir::RoundMode;
 using xe::cpu::hir::Value;
 
 // Good source of information:
-// http://mamedev.org/source/src/emu/cpu/powerpc/ppc_ops.c
+// https://github.com/mamedev/historic-mame/blob/master/src/emu/cpu/powerpc/ppc_ops.c
 // The correctness of that code is not reflected here yet -_-
 
 // Enable rounding numbers to single precision as required.