Rename Relay to Inject state

[tsurdilo]

Renames Relay state to Inject state so it's name makes more sense.

After getting some info from community, one of the bigger complaints was that noone understood what the name "Relay" means in relay state. It is a state that injects static data into the state data input. So from that changing:

Relay State / inject property to Inject State / data property

to clearly describe that this is a state that "injects" "data".

[cathyhongzhang]

Is this "injected data to the state" in addition to data passed to this state

1. from the previous state output
2. from the previous state's functions' output
3. from external events if this state is an event state

[tsurdilo]

@cathyhongzhang Hi :) yes the inject state has state data input like all the others. It injects additional static data into its state data. This data is merged with its existing data input.

[cathyhongzhang]

LTGM