COMMON: Make the two INI save file functions take a String reference
SCUMM: Make all HE saves prepend the target name

This makes HE follow the ScummVM convention of using the target name everywhere. It also fixes having more than one team in both soccer and football.

Loading old saves will still work and they will be tried if the newer save names are not found.
WINTERMUTE: Adding more detection entries.
DC: Workaround for usleep prototype mismatch
DC: Silenced some stupid warnings
GRAPHICS: Fix computation of addA in darkenFill()

The old computation had rounding issues, causing alpha to leak into
the red (usually) component.  There's a much easier way to compute it
that does not lead to such problems:  What should really happen is that
the two top bits of the A component should be set to 1 (thus adding
75% alpha).  So compute it that way for speed and precision.
GRAPHICS: Fix dest alpha formula in blendPixelPtr

The original alpha computation formula had a problem:  If something was
drawn on top of a pixel that was already fully opaque, there would be
an overflow in the computed alpha, and the destination alpha would be
truncated to 0 (fully transparent).

In commit 264ba4a9 this formula was replaced with another one, which
did not have overflows but also was not correct.

This commits introduces a new formula, where the rounding errors have
been turned in another direction; drawing a fully opaque pixel on top
of a transparent one would result in a pixel which is almost, but not
fully, opaque.  However, this is no problem in practice, since drawing
fully opaque pixels can be achieved with much less code as a special
case, so add that (also improves rendering speed).
ANDROID: Set correct blending function

Overlays with alpha channel in ScummVM use pre-multiplied alpha.
Thus, is it necessary to set the source blend function to ONE, not
SOURCE_ALPHA.

While there is no firm decision on the texture format to be used to
cursors, make sure to set the key color to R=G=B=A=0.0, so that it
can be used with either pre-multiplied or non-pre-multiplied blending.
FULLPIPE: Implement preloadCallback()
FULLPIPE: Fix warning
FULLPIPE: Fix warning
CONFIGURE: Add workaround for GCC bug in Dreamcast toolchain.
TEENAGENT: Fix missing callback for examining first haystack.

This fixes bug #6492 "TEENAGENT: Engine abort when using hay."
FULLPIPE: Implement MovTable destructor
FULLPIPE: Started implementing MGM::calcLength()
FULLPIPE: Implement MGM::calcLength()
WINTERMUTE: Add detection for french, italian, spanish and czech versions of Dirty Split.
SDL: Avoid having SDL_SRCALPHA set even if we have alpha in the pixelformat.
Merge pull request #418 from JenniBee/md5s

WINTERMUTE: Adding more detection entries.
NEVERHOOD: Set engine to 'built by default'