Partially make MeterPrimitive.md.
Partially make MeterPrimitive.md.

sugiuraii/WebSocketGaugeClientNeo,sugiuraii/PixiJS-Websocket-typescriptStudy,sugiuraii/WebSocketGaugeClientNeo,sugiuraii/PixiJS-Websocket-typescriptStudy,sugiuraii/WebSocketGaugeClientNeo,sugiuraii/PixiJS-Websocket-typescriptStudy