poolaccum uses permute API (not yet documented)

Function is not made parallel ready, but it uses permute API.
The permute "control" is returned as an attribute, but not
printed or used in any way.

(cherry picked from commit cc001305a66376166c1a8a1d7a125cea1cea726a)
Wait till number of permutations is evaluated before you use it

(cherry picked from commit e84cfa84744f4ffb574d74cdaf06eb64d80e32f9)
estaccumR uses permute API and is parallel ready

(cherry picked from commit 873e8f32ee9753b433020142f6b42799a9471d69)
parallel processing in estaccumR

(cherry picked from commit f5fbba392609a2d37ad68adff1d15423e6c54780)
Document the use of permute API and parallel processing

(cherry picked from commit 5cbc2865f5b13fd9f3bd950bf50381588e8fc688)
specaccum uses permute API

(cherry picked from commit 2f2a3ceadb712be8bf61017853d9946077ef20b9)
renyiaccum uses permute API

(cherry picked from commit f623cf9bb37266951fbb06f0836d2c42c4be1861)
tsallisaccum uses permute API

(cherry picked from commit 794c0633b371eb044de95a8132d0acbb9d468fb7)
fix slack coding

(cherry picked from commit 07a80ca2c880f5040e4033251321f6c5f105c2dd)
Return "control" attribute when permute API was used

(cherry picked from commit 10a422b7d3b889e16bdc07c1e3d1cf1605691eda)