Use modulemd version 2 and update packages

mongodb.yaml

@@ -1,6 +1,6 @@
 ---
 document: modulemd
-version: 1
+version: 2
 data:
     summary: MongoDB Module
     description:  Mongo from humongous is a high-performance, open source, schema-free
@@ -18,13 +18,10 @@ data:
     license:
         module: [MIT]
     dependencies:
-        buildrequires:
-            bootstrap: f27
-            boost: 1.64
+      - buildrequires:
+            platform: [f28,f29]
         requires:
-            platform: f27
-            perl: 5.26
-            boost: 1.64
+            platform: [f28,f29]
     references:
          community: https://docs.pagure.org/modularity/
          documentation: https://github.com/container-images/mongodb/
@@ -53,24 +50,23 @@ data:
         rpms:
             mongodb:
                 rationale: MongoDB package.
-                # mongodb-3.4.6-3.fc27
-                ref: a655c1f4dd559a5bd0f0142330770f23c2c0d0c9
+                ref: 3.6
                 buildorder: 2
             python-pymongo:
                 rationale: MongoDB dependecy for running testsuite.
-                ref: f27
+                ref: f28
                 buildorder: 3
             yaml-cpp:
                 rationale: MongoDB dependency.
-                ref: f27
+                ref: f28
                 buildorder: 0
             mozjs45:
                 rationale: MongoDB dependency (not used on x64_64,s390x,aarch64 and ppc64le).
-                ref: f27
+                ref: f28
                 buildorder: 0
             gperftools:
                 rationale: MongoDB dependency (should go to separate module).
-                ref: f27
+                ref: f28
                 buildorder: 0
             python-pymongo:
                 rationale: MongoDB dependecy (F26 branch does not require mongodb for tests).