lscert | Add support for parsing/displaying CSR files

[atc0005]

Overview

openssl command:

openssl req -noout -text -in <CSR_FILE>

References

• https://golang.org/pkg/crypto/x509/#ParseCertificateRequest
• https://stackoverflow.com/questions/56038083/check-if-x509-certificate-matches-a-certificaterequest-csr
• https://stackoverflow.com/questions/5215771/how-can-i-check-if-the-certificate-file-i-have-is-in-pem-format
• https://stackoverflow.com/a/47765718/903870
• https://stackoverflow.com/a/38893118/903870
• https://8gwifi.org/PemParserFunctions.jsp

[atc0005]

Note to self: Make sure that the public key details are listed.