Feature request: A way to save current data from flow and to insert data to flow

**Is your feature request related to a problem? Please describe.**
Currently there is no simple way to save values from operations to use in later operations

**Describe the solution you'd like**
- A feature to save the current value from the flow to use later in the flow preferable with a nameable variable (Store operation)
- A feature to load variables into the current flow (Load operation)
- Ability to use the variables as arguments the same way that it is possible with the Register values

The current way I handle this is by using Register to save values and Find/Replace to insert values, example recipe below
[Link to recipe](https://gchq.github.io/CyberChef/#recipe=Comment('Saves%20input%20as%20$R0')Register('(%5B%5C%5Cs%5C%5CS%5D*)',true,false,false)Pseudo-Random_Number_Generator(32,'Hex')Comment('Saves%20random%20number%20as%20$R1')Register('(%5B%5C%5Cs%5C%5CS%5D*)',true,false,false)Comment('Loads%20$R0%20(Input)')Find_/_Replace(%7B'option':'Regex','string':'.%2B'%7D,'$R0',true,false,true,false)Comment('Xors%20the%20Input%20with%20Random%20Number%20$R1')XOR(%7B'option':'Hex','string':'$R1'%7D,'Standard',false)&input=SXMgdGhlcmUgYW4gbW9yZSBlbGVnYW50IHdheT8)