Bug Report for backend SSL enable
There is running error after enable backend SSL.
I've enabled ssl here
https://github.com/moneroexamples/openmonero/blob/1be824a12d803f211a437298cb763aee12e4484c/config/config.json#L62

Generate ssl-key and ssl-crt with below command on Ubuntu
`openssl req -newkey rsa:2048 -keyout server.key.pem -x509 -days 3650 -out server.cert.pem`
Generated dh-pem with below command on Ubuntu.
`openssl dhparam -out dh2048.pem 2048`

When I start openmonero, I was able to see there is error like below

2019-01-13 15:09:33,700 INFO  [default] Page size: 4096
2019-01-13 15:09:34,700 INFO  [openmonero] OpenMonero is starting
2019-01-13 15:09:34,700 INFO  [openmonero] Using blockchain path: /home/jason/.bitmonero/lmdb
2019-01-13 15:09:34.702     7f8541a69280        INFO    blockchain.db.lmdb      src/blockchain_db/lmdb/db_lmdb.cpp:544  DB map size:     79372144640
2019-01-13 15:09:34.702     7f8541a69280        INFO    blockchain.db.lmdb      src/blockchain_db/lmdb/db_lmdb.cpp:545  Space used:      71066189824
2019-01-13 15:09:34.702     7f8541a69280        INFO    blockchain.db.lmdb      src/blockchain_db/lmdb/db_lmdb.cpp:546  Space remaining: 8305954816
2019-01-13 15:09:34.702     7f8541a69280        INFO    blockchain.db.lmdb      src/blockchain_db/lmdb/db_lmdb.cpp:547  Size threshold:  0
2019-01-13 15:09:34.702     7f8541a69280        INFO    blockchain.db.lmdb      src/blockchain_db/lmdb/db_lmdb.cpp:549  Percent used: 0.8954  Percent threshold: 0.9000
2019-01-13 15:09:34.734     7f8541a69280        INFO    blockchain.db   src/blockchain_db/blockchain_db.cpp:371 Database is opened read only - skipping fixup check
2019-01-13 15:09:34.735     7f8541a69280        INFO    blockchain      src/cryptonote_core/blockchain.cpp:445  59872331213
2019-01-13 15:09:34,735 INFO  [openmonero] Blockchain monitoring thread started
2019-01-13 15:09:34,737 INFO  [openmonero] Current blockchain height: 1748147, no of mempool txs: 2
2019-01-13 15:09:34,742 INFO  [openmonero] Connected to the MySQL
2019-01-13 15:09:34,742 INFO  [openmonero] MySQL ping thread started
2019-01-13 15:09:34,743 INFO  [openmonero] JSON API endpoints published
terminate called after throwing an instance of 'std::invalid_argument'
  what():  Argument is not a valid URI: /home/jason/Desktop/Work/certs/server.key
Aborted (core dumped)