Added ReplayBird Integration

[fizerkhan]

What does this PR do? This is for adding our product ReplayBird in Segment integration. https://www.replaybird.com/

Are there breaking changes in this PR? No

Any background context you want to provide? Our product is ReplayBird - Web behavior analytics with Screen Recordings

Is there parity with the server-side/android/iOS integration components (if applicable)? No.

Does this require a new integration setting? If so, please explain how the new setting works Yes, we need site key.

You can find your site key on the ReplayBird Site integrations page by logging into your account, clicking the integrations in the side bar, and looking in the tracking code for 'apiKey'

Links to helpful docs and other external resources

ReplayBird
https://www.replaybird.com/

User journey & engagement analysis for websites

### How ReplayBird works

ReplayBird provides complete user journey & engagement analysis for websites. Its JavaScript snippet must be installed on all of the pages of your site where you want to capture customer engagement. ReplayBird also offers custom code for sites hosted by many popular CMS', including Squarespace, Wix, Joomla, Drupal, and others.

* Provides user session recordings and replay
* Advanced filtering options & custom recording segmentation
* Sharing recordings
* Automatic event tracking, Javascript errors & comprehensive events management
* Ability to add custom events & properties for advanced evaluation via event breakdowns - advanced events segmentation
* Enables definition of conversion funnels with complete customer journey recordings
* Global data analysis overview via Dashboard
* Supports user identification methods

### Text for ReplayBird Setting page in segment

ReplayBird offers a full set of user experience tools for your website: session recordings, events and funnel analytics.

[fizerkhan]

I am waiting for the review