Reduce number of trials.
Add tests.
Internal change.
Rename some operators that use key mapper function,  to "xxxBy".
Rename some quantifier operators that test number of elements,  to "hasXXX", to comply with Java naming convention.
Rename sequenceEqual to equalsSequentially, to comply with Java naming convention.
Introduce type parameter on (last)IndexOf for type safeness.
Rename some quantifier operators that test number of elements,  to "hasXXX", to comply with Java naming convention.
Correct missing javadoc items.
Add javadoc and test of the pad operator.
Implement pad operator of ParallelSeq.
Rename eachCons to slide which is more descriptive.
Optimize buffer & bufferWithPadding.
Add examples in javadoc.
Add permutations operator.