mongod: add page (#1525)

pages/common/mongod.md

@@ -0,0 +1,15 @@
+# mongod
+
+> The MongoDB database server.
+
+- Specify a config file:
+
+`mongod --config {{filename}}`
+
+- Specify the port to listen on:
+
+`mongod --port {{port}}`
+
+- Specify database profiling level. 0 is off, 1 is only slow operations, 2 is all:
+
+`mongod --profile {{0|1|2}}`