feat: Implement support for importing certificates

chore: Remove obsolete model
wip: Create first working test case for cert import
wip: Generate basic certRequest from given cert files
wip: Start work on being able to import certificates
chore: Update gitignore

src/main/java/de/mlessmann/certassist/openssl/CertificateSubject.java

@@ -7,10 +7,13 @@ import lombok.Getter;
 @Builder
 public class CertificateSubject {
 
+    private String commonName;
     private String emailAddress;
     private String organization;
     private String organizationalUnit;
     private String country;
     private String state;
     private String locality;
+
+    public static class CertificateSubjectBuilder {}
 }