Validate file extension with magic number and get files extension.

Actions:

- GetMimeFromBinary: Get MIME Type from Binary

input: "file" (binary)

output: "mimeType" (text)

output: "error" (text)

- ValidateFileExtension: Validate File Extension

input: "file" (binary)

input: "fileName" (text)

output: "valid" (boolean)

output: "errorMessage" (text)

output: "mimeType" (text)