Make Multiplayer Template an item owned by SIG

[lmbr-pip]

• Add Multiplayer project template as something owned by SIG
• Update triage guide to look for issues with template
• Fixes some formatting issues in charter and adds some links to blank sections

Signed-off-by: Pip Potter 61438964+lmbr-pip@users.noreply.github.com

[lmbr-pip]

Both SIG chair(s) agree with change of scope, no objections from sig-network members. Accepting change on behalf of SIG.