Cleaned up other docs in preparation for alpha-testing announcement
Created `math/utils' module for stuff that doesn't go anywhere else (e.g.
FFT scaling convention, max-math-threads parameters)
Reduced the number of macros that expand to applications of `array-map'
Added `flvector-sum', defined `flsum' in terms of it
Reduced the number of pointwise `flvector', `flarray' and `fcarray' operations
Reworked `inline-build-flvector' and `inline-flvector-map' to be faster and
expand to less code in both typed and untyped Racket
Redefined conversions like `list->flvector' in terms of for loops (can do
it now that TR has working `for/flvector:', etc.)
Refactored many of the fold functions (e.g. `array-axis-andmap' is gone,
replaced by short-cutting `array-axis-and', which is sufficient because the
result of `array-map' is non-strict; added `array-count', `array-all-fold';
removed `array-all=' and friends)
Turned common folds into macros (preserves return types better, speeds up
compilation time)
Exposed a safe variant of `unsafe-array-axis-reduce'
clean up build
Moved `float-complex?' and `number->float-complex' to `math/base',
documented them
Documented `flexpt1p'
Removed `samples->immutable-hash' (not covariant anyway; not going to
use hashes)
Replaced pointwise operators with macros that expand to applications of `array-map'; allows more precise return types and reduces compilation time
Changed literal array syntax to use #() to delimit rows instead of [] (still suggest using square parens, though)
Minor refactoring
Fixed a macro so that the only problem with "array-tests.rkt" now is that typed/rackunit is b0rked
