Add accepted RFCS to RFC archive

[lmbr-pip]

Add two recently accepted RFCs to sig-network archive

Brings in the following RFCS, accepted by SIG on Oct 5th 2021

• RFC: Scriptable Network Input #6

• RFC: Hierarchical Network Entities #5

• Propose naming documentation

[sptramer]

@lmbr-pip Would recommend putting this in the o3de/rfc repo perhaps? If you want to keep it in sig-networking we should have a similar PR for each sig

[lmbr-pip]

@sptramer - Most SIGs seem to be keeping their SIGs locally ie:

• Sig content: https://github.com/o3de/sig-content/tree/main/rfcs
• sig platform: https://github.com/o3de/sig-platform/tree/main/rfcs

We already seem to be deviating from any norms ;)

Proposal is to use the 'standard' O3DE RFC naming (https://github.com/o3de/rfcs/tree/main/sigs/sig-network), but just adding a friendly name to the file name to aid discovery. Beyond that we are not proposing a new standard for actual RFC naming.

[lmbr-pip]

Am going to bring RFC archiving with SIG leads. For now submitting these as is, can always quickly rename once we get cross SIG direction in place.