refactor: replace obsolete methods in comments / test descriptions

[ytjmt]

The following methods are now obsolete but still used in comments and test descriptions. In this PR, I've replaced them with new ones.
ref: 56bfe0a dc8ee81

• useRawBody => readRawBody
• useBody => readBody
• useCookies => parseCookies ( already fixed by test: replace useCookies with parseCookies in describe #314 )
• useCookie => getCookie
• useQuery => getQuery
• useMethod => getMethod

[pi0]

Thanks!