QA-720 - added 4 new data endpoints

***Changes***
Added:
```
/client/projects/data/emoticons
/client/projects/data/hashtags
/client/projects/data/mentionedauthors
/client/projects/data/urls
```
Added Gem locally and ran the API tests that use the endpoints. working as expected.

***Rubcop***
107 files inspected, no offenses detected
Could we change `mentioned_authors` to `MentionedAuthors`