Add Vector/Matrix classes, threaded task class, Color class

Add Vector/Matrix classes from SRE (originally based on code by Eric
Lengyel), including SIMD optimizations. Also includes Color class.

Add dstTaskScheduler class for maintaining a set of threads.

Rename dstDynamicArray::AllocatedSize() to Capacity().

Update README.

Make several improvements and fixes relating to shared library,
dependencies and Makefile, and add pkgconfig file . The library
should now be properly configured as an installed shared library.

Move installed header files into /usr/include/DataSetTurbo/.

Bump version to 0.3.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>
Expand dynamic array class with new member functions

Expand the dynamic array class types with new member functions,
including adding multiple elements (from buffer or another array) and
adding elements without a capacity check.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>
Improve vector classes, SIMD functions, dynamic array class

Fix bug in dstDynamicBaseArray, add optimized variants for adding
small or large buffer or dynamic array to an existing dynamic array,
and add RemoveHead function.

Add sreMemory.h module with memcpy and memset (ARM) implementations,
including assembler-optimized ARM memset. Add Makefile.conf settings
PREFER_LIBC_MEMCPY and UNALIGNED_MEMORY_ACCESS.

Complete optimization of dstVectorMath.h, using template classes for
all vector types.

Make naming of simple math functions like dstInvSqrt(float) more
consistent, implement AlmostEqual using template function.

Make several improvements/bug fixes to SIMD support, including
enforcing alignment restrictions for most SIMD functions that
process vectors.

Signed-off-by: Harm Hanemaaijer <fgenfb@yahoo.com>