Collator for the "adder" (formerly basic-add) parachain and various small fixes (#438)

* update basic_add wasm

* wasm feature and collator feature

* move test parachains around a little

* fix wasm build for basic_add

* move basic_add to adder, introduce README

* minimal basic_add collator

* ensure collator messages are sent in the right order

* more logging

* route consensus statements to all peers

* minor bugfixes for parachains

* genesis builder accounts for parachain heads

* fix parachains tests

* targets for txpool

* tweak runtime + collator

* fix version in adder-collator

* consistency for overflowing

* adjust comment

* fix stable test run

* remove dummy registration test

* final grumbles

substrate/Cargo.toml

@@ -32,6 +32,9 @@ members = [
 	"polkadot/transaction-pool",
 	"polkadot/service",
 
+	"polkadot/test-parachains/adder",
+	"polkadot/test-parachains/adder/collator",
+
 	"substrate/bft",
 	"substrate/cli",
 	"substrate/client",
@@ -77,6 +80,7 @@ members = [
 ]
 exclude = [
 	"polkadot/runtime/wasm",
+	"polkadot/test-parachains/adder/wasm",
 	"demo/runtime/wasm",
 	"substrate/executor/wasm",
 	"substrate/pwasm-alloc",
@@ -92,4 +96,4 @@ is-it-maintained-open-issues = { repository = "paritytech/polkadot" }
 
 [profile.release]
 # Substrate runtime requires unwinding.
-panic = "unwind" 
+panic = "unwind"