Codecov: Only test slate, slate-html-serializer and slate-plain-serializer (#2186)

* Only test slate models

* test slate-plain and slate-html models

* Fix travis

.nycrc

@@ -4,7 +4,7 @@
   "all": true,
   "extension" : ["js"],
   "cache": false,
-  "include": ["**/src/**"],
+  "include": ["packages/slate/src/**", "packages/slate-html-serializer/src/**",  "packages/slate-plain-serializer/src/**"],
   "reporter": [
     "html",
     "lcov",

.travis.yml

@@ -10,6 +10,7 @@ cache: yarn
 env:
   # Do two runs, one for testing and one for linting.
   matrix:
+    - TEST_TYPE=test:coverage	
     - TEST_TYPE=lint:eslint
     - TEST_TYPE=lint:prettier
 
@@ -27,4 +28,5 @@ script:
   - |
     set -e
     yarn $TEST_TYPE
+    if [[ $TEST_TYPE == 'test:coverage' ]]; then yarn codecov; fi	
     set +e