Add 2nd newline to some Contents.m files and others.

Octave 3.7 has trouble locating some top level help files, aka
Contents.m files if they don't end in 2 blank lines at the end.
Bug? Feature? Who knows?
PsychImaging: Simplify use for non-task case and error case.

* Allow 'PrepareConfiguration' to be called when a previous
  configuration phase hasn't ended yet, e.g., due to some
  error during PsychImaging('openwindow'), the most trivial
  case being a sync failure at openwindow time.

  Output a warning and just restart configuration phase, instead
  of error abort.

  -> Should make this most common case easier to handle.

* Allow call of 'OpenWindow' without a previous 'PrepareConfiguration'.
  Call 'PrepareConfiguration' implicitely if not called before openwindow.

  This allows to use PsychImaging('OpenWindow', ...); as a drop in
  replacement for Screen('OpenWindow', ...); without need for a
  PsychImaging('PrepareConfiguration') first. Called this way, it will
  mostly behave like a regular Screen('openwindow') call, without
  processing any task specs.

  -> Encourages use of PsychImaging('OpenWindow') instead of Screen('OpenWindow')
     in future scripts, so users get in the habit of taking advantage of it and
     less explanation for the replacement procedure is needed.

* Make PsychImaging subfunction name matching case-insensitive via strcmpi().
Screen('ColorRange'): Optionally apply [0-maxvalue] to Screen('MakeTexture');

Screen('ColorRange') or PsychImaging('NormalizedHighResColorRange'); now
optionally accept a new flag 'alsoApplyToMakeTexture'. If set to 1, then
Screen('MakeTexture') will apply the colorRange setting also for standard
low precision 8-Bit integer textures if the input image matrix is provided
in double precision format instead of uint8, ie., as typically created by
Matlab/Octave matrix operations. This is achieved by scaling the double
input values properly before casting to uint8. Of course range limit to
[0; maxvalue] still applies, and standard textures are still limited to
8 bit or 256 levels.

-> This makes behaviour for standard precision 8-Bit textures consistent
   with behaviour of other Screen() drawing commands if a non-standard
   colorRange is selected. Especially useful for a normalized [0.0; 1.0]
   range, for specifying stimuli in a device independent normalized intensity
   range.

-> Opt-In: Not enabled by default to retain backwards compatibility.

-> Screen for 64-Bit Octave on Linux rebuilt and tested.
Linux Matlab makefiles: Make them work with Matlab R2012a

Need to escape our *.c and *.cc globs with "", so mex compiler
of R2012a+ doesn't bail.

-> linuxmakeit_ubuntugutsy.m and linuxmakeit64_ubuntugutsy.m
   for 32/64-Bit Matlab on Linux modified.
New function PsychDefaultSetup()

PsychDefaultSetup is supposed to reduce boilerplate code at the
top of typical scripts. It performs a couple of frequently needed
setup steps. A mandatory 'featureLevel' parameter tells how to
setup and also how to choose defaults:

Level 0: Only execute AssertOpenGL
Level 1: Additionally execute KbName('UnifyKeyNames').
Level 2: PsychImaging('AddTask','General','NormalizedColorRange', 1)

The latter one, if windows are opened with PsychImaging('OpenWindow')
will switch the window to an unclamped colorrange of [0;1], and apply
that color input range also to standard 8 bpc integer textures if the
imageMatrix is passed to Screen('MakeTexture', window, imageMatrix, ...)
as a double class matrix. This allows use of a unified normalized 0-1
range for clearer code and independence of output display device
color resolution.

-> New function PsychDefaultSetup.m
-> PsychImaging.m extended to honor Level 2 setting of PsychDefaultSetup.m
Screen: Make Screen('ColorRange') less verbose for unclamped color range.

As unclamping the color range is now default behaviour if
PsychDefaultSetup(2) is used, we don't want all the info
about color clamping precision and how to test it anymore.
Way too much clutter.

-> Screen mex files for 64-Bit Octave and 64-Bit Matlab on Linux rebuilt
   and tested.

-> This is build against R2012a, so needs a recompile against our standard
   R2007a for consistency before release.
PsychDebugWindowConfiguration: Disable high precision timestamping on all OS'es.

Not only on OSX, but also on Windows and Linux. This is needed to
avoid timestamp warning clutter on modern setups if transparent
onscreen windows are on.

Also clean up help text a bit.
WhiteIndex: Take PsychDefaultSetup(2) into account.

At featureLevel 2, a normalized colorrange is requested, so
assume WhiteIndex == 1.0 if it can't get queried from an
already open and eligible window.
Repair AlphaImageTutorial: Path to image was wrong.