README.md: Document expected use of lowerCamelCase (#1009)
README.md: Document expected use of lowerCamelCase (#1009)

* Document expected use of lowerCamelCase

* upcase first letter of sentence, add the.

Changes requested by @Insti

jmluy/x-common,rpottsoh/x-common,jmluy/x-common,ErikSchierboom/x-common,ErikSchierboom/x-common,exercism/x-common,exercism/x-common,jmluy/x-common,petertseng/x-common,rpottsoh/x-common,petertseng/x-common