Refactor test package and some field types

Fairly big test refactor and changing some of the fields from pointers

test/invalid-config-unknown-alert.hcl

@@ -0,0 +1,12 @@
+check_interval = "1s"
+
+monitor "Command" {
+  command = ["echo", "$PATH"]
+  alert_down = ["not_log"]
+  alert_every = 0
+}
+
+
+alert "log" {
+  command = ["true"]
+}