Attempt to fix bugs related to empty vecs

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

Cargo.lock

@@ -1098,6 +1098,15 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b93853da6d84c2e3c7d730d6473e8817692dd89be387eb01b94d7f108ecb5b8c"
 
+[[package]]
+name = "nonempty"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "303e8749c804ccd6ca3b428de7fe0d86cb86bc7606bc15291f100fd487960bb8"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "nonzero_ext"
 version = "0.3.0"
@@ -1316,6 +1325,7 @@ dependencies = [
  "lazy_static",
  "log",
  "log4rs",
+ "nonempty",
  "regex",
  "reqwest",
  "serde",