gles2n64: Fix big regression - should not clear color buffer.

in OGL_ClearDepthBuffer function - fixes Turok 1 (graphics were
just black before), fixes Banjo Kazooie (whenever HUD appeared,
screen turned black - fixed now), fixes Waverace 64 (intermission
screens had a black background), and more

[cherry-pick from https://github.com/libretro/mupen64plus-libretro/commit/2b57b5183941762e12fffcd840ef47680eb5592b]
gles2n64: Fix early return out of gSPBgRectCopy N64 SDK function.

This fixes the topdown prerendered background in Link's hut (Zelda
OOT). Previously this background would be a bunch of polygons on a
green screen.

Also helps get Biohazard 2 ingame with glN64. It would previously crash
hard.
doc: Updated changelog.

Confirmed OoT and all 3 Turok series on 2012 Nexus 7.  Didn't confirm
Banjo Kazooie or Waverace.
Add credits to the recent changelog additions.

Considering we didn't directly fix it, it's only fair that the original person that uncovered/fixed the bug get his name credited.
doc: Update changelog.
r4300: Fix Perfect Dark crashes/freezes.

Had a look at this issue -
http://code.google.com/p/mupen64plus/issues/detail?id=553

Implemented the proposed fix on my own and that got rid of the spurious
crashes for me.  BTW - Misschief Makers is another game that reports
this warning "two events of same type interrupt queue". Anyway,
returning when that happens gets rid of the crashes in PD.

[cherry pick from
https://github.com/libretro/mupen64plus-libretro/commit/12133422f75aa3f88ef5decc820402e894371adc]

littleguy note: You might need to delete any pre-existing .eep and .mpk
files from the SlotSaves directory and reset the game the first time
you run with this fix.  More discussion here:
http://www.paulscode.com/forum/index.php?topic=1042
doc: Update changelog.
Merge branch 'master' into lifecycle-fixes
libs: Added apache commons codec library.

For computing MD5 checksums on Java side (needed for version 3.0).