Improve find's @safety
Fix unpredictableSeed so that rndstuff can be used in @safe code

Allows:
1) canFind's tests to be @safe
2) allows the remainder of find's tests to be @safe
map should be @safe
cycle should be @safe
equal should be @safe
sequence should be @safe
cmp should be @safe
minPos should be @safe
mismatch should be @safe
livenshteinDistance should be @safe
copy should be @safe
swapRanges and reverse should be @safe
bringToFront should be @safe
remove should be @safe
uniform should be @safe
partition should be @safe
topN should be @safe
cache and reduce should be @safe
fill should be @safe
filter should be @safe