Make whether to use OpenCL or not a global option

Add a toggle to the "General" page.

Change-Id: If35b1472032706b09a3bc3499c55cbd3ac2e13ac
Move clew into a library of its own

Change-Id: Ifb7e86b078bd549506a9cc1b9ce9fc22fffc5eec
Need -lrt for clock_gettime() with older glibc versions

Change-Id: Id134b05de3a81dd246baf8743c32fa8eb1e37935
Need -lrt for clock_gettime() with older glibc versions

Change-Id: I6ccd990ba71867f0ff96ad06cf5a9e7c98c93657
Work in progress: Move Calc-independend OpenCL configuration out of sc

Intermediate commit. More changes will follow: The device selection
logic needs to be moved, too. (And cleaned up.) Instead of the
separate formulacalculationoptions dialog we should simply have a
normal options page for those OpenCL-related settings that will remain
purely Calc-specific, like the formula opcode subsetting.

Change-Id: Id60d95e80d377cbbf5780beb473b221bce06b5e5
Add the "Test" button back

This functionality is Calc-specific and will stay in the Calc part of
the options. Let's not give the false impression that it would be
going away. (How it looks and works now is not final.)

Change-Id: Ic2f783a6fd07de89eec7d7e685364dad71243b4b
Try to fix MSVC build

Change-Id: I24c48d2540a8cb7d2a823862d53cddf90d41f94a
Fix OpenCL-less build

Change-Id: I36a0151640067e3d040ebf46784bdb8c534153e1
Add a README file

Change-Id: Id0f8a146ca90efe6f84c7a0c377ad3f83ba7da8d
Fix OpenCL-less build

Change-Id: I8e049a6df5946344110b38887301d186991a475d
Fix OpenCL-less build harder

Change-Id: I1627f534505c735455c50f9b4f6e4d1c698ab9d2
Move more Calc-independent OpenCL stuff from the sc to the opencl module

No cleanups yet. Just removed the "sc" namespace parts now when this stuff is
no longer Calc-specific. There is still horribly confusing use of the same
OpenCLDevice name for both a class and as a namespace, for instance. And the
OpenCLDevice class has only public static members even, so effectively it acts
as just a namespace anyway... Etc.

Change-Id: Idc5f30a721df0101426c676f04a85e02c5dc8443
WaE: variable 'bSetOpenCL' set but not used

Change-Id: I897accf5b4259a4a01198118421abaa55465207e
Use correct SAL_INFO log area

Change-Id: I47e6dcf18fe141b8dba33a8c3cd83f80950045cd
Need -lrt for clock_gettime() with older glibc versions

Change-Id: I4651f74a89b8707cbf0ebdd3b950df3a5b99177a
Clean up confusing OpenCL code a bit

Get rid of the silly OpenCLDevice class that had only static members. We can
as well just use namespacing. Remove functions only used internally in
openclwrapper.cxx from the now public openclwrapper.hxx header.

Change-Id: If7336edd262c772564dc13e64113d72d0b52428c
The OpenCLEnv struct is used only inside openclwrapper.cxx

Change-Id: I95fbee302213e6ced469dd7a2a1c254178159357
Put the KernelEnv struct inside the opencl namespace, too

Change-Id: I33d51b0e30445c34c792210e7c656c1d48159019
scui needs the opencl library at least on Windows

Change-Id: I4183b957d59bb81b8df7a5f51418be94c879b3fe
The compiler-generated dtor is good enough, no need for this

Change-Id: Ib72e0df4ac3ca90d440a32359e711d77e758cca0