Explicit errors in e2e repo tests (#361)

- spec:e2e will not fail silently anymore if ESLint sees a fatal parsing syntax error.
- Fix RepoInfo config for electron-react-boilerplate
- Fix snapshot

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* fix typescript error

* fix silent error

* shorten

* fix linting file patterns

* error if fatal parsing problem

* fix electron-react-boilerplate config

* update snapshot

* update message to template

* clarify fatal eslint error

* add gif to binary

.gitattributes

@@ -4,3 +4,4 @@
 *.jpeg binary
 *.ico binary
 *.icns binary
+*.gif binary