Clean Phragmén Equlise API (#5452)

* Clean phragmen API and equalise()

* Stabilize new api

* Fix phragmen fuzzers

* More fixes

* Make fuzzers reproducible

* improvements

* Make equalize update assignments as well.

* total function for staked_assignment.

* Fix fuzzer build

* remvoe TODO

* Fix a bunch more.

* clean stray debug stuff

* Update primitives/phragmen/src/lib.rs

Co-Authored-By: thiolliere <gui.thiolliere@gmail.com>

* fix range function

* fix number generator

Co-authored-by: thiolliere <gui.thiolliere@gmail.com>

substrate/Cargo.lock

@@ -7515,6 +7515,17 @@ dependencies = [
  "syn 1.0.17",
 ]
 
+[[package]]
+name = "sp-phragmen-fuzzer"
+version = "2.0.0-alpha.5"
+dependencies = [
+ "honggfuzz",
+ "rand 0.7.3",
+ "sp-phragmen",
+ "sp-runtime",
+ "sp-std",
+]
+
 [[package]]
 name = "sp-rpc"
 version = "2.0.0-dev"