change: Move features to enable WASM-compilation

We move all the `parallel` features of deps under a `parallel` feature
for the crate which doesn't activate them by defaul.

Cargo.toml

@@ -18,12 +18,12 @@ num-bigint = { version = "=0.4.3", default-features = false, features = ["rand"]
 
 # ZKP Generation
 ark-crypto-primitives = { version = "=0.4.0" }
-ark-ec = { version = "=0.4.1", default-features = false, features = ["parallel"] }
+ark-ec = { version = "=0.4.1", default-features = false }
 ark-ff = { version = "=0.4.1", default-features = false, features = ["parallel", "asm"] }
-ark-std = { version = "=0.4.0", default-features = false, features = ["parallel"] }
+ark-std = { version = "=0.4.0", default-features = false }
 ark-bn254 = { version = "=0.4.0" }
-ark-groth16 = { version = "=0.4.0", default-features = false, features = ["parallel"] }
-ark-poly = { version = "=0.4.1", default-features = false, features = ["parallel"] }
+ark-groth16 = { version = "=0.4.0", default-features = false }
+ark-poly = { version = "=0.4.1", default-features = false }
 ark-relations = { version = "=0.4.0", default-features = false }
 ark-serialize = { version = "=0.4.1", default-features = false }
 
@@ -52,7 +52,8 @@ name = "groth16"
 harness = false
 
 [features]
-default = ["wasmer/default", "circom-2", "ethereum"]
+default = ["parallel", "wasmer/default", "circom-2", "ethereum"]
+parallel = ["ark-ec/parallel", "ark-ff/parallel", "ark-std/parallel",  "ark-groth16/parallel", "ark-poly/parallel"]
 wasm = ["wasmer/js-default"]
 bench-complex-all = []
 circom-2 = []