Feat: Add RNNs forward and backward passes (#32)

* Add Dropout and begin to work on RNNs

* Add RNNs basic functionalities

* Add RNNs

Author: frjnn

crates/cudnn/Cargo.toml

@@ -5,4 +5,5 @@ name = "cudnn"
 version = "0.1.0"
 
 [dependencies]
+bitflags = "1.3.2"
 cust = {version = "0.2.2", path = "../cust"}