Add content blocking API call with demo

[seeReadCode]

• [ ] demo button in example for block user
• [ ] demo button in example for block recording
• [ ] demo button in example for flag

something like...

        let assetID = String(currentAsset.assetID)
        let rwf = RWFramework.sharedInstance

        let moreModal = UIAlertController(title: "More actions", message: "", preferredStyle: UIAlertControllerStyle.alert)

        //Block Recording
        //TODO mark completed
        moreModal.addAction(UIAlertAction(title: "Block Recording", style: UIAlertActionStyle.default, handler: {(alert: UIAlertAction!) in
            rwf.apiPostAssetsIdVotes(asset_id: assetID, vote_type: "block_recording",
                success: { (data) -> Void in
                }, failure:  { (error) -> Void in
            })
        }))

        //Block User
        moreModal.addAction(UIAlertAction(title: "Block User", style: UIAlertActionStyle.default, handler: {(alert: UIAlertAction!) in
                rwf.apiPostAssetsIdVotes(asset_id: assetID, vote_type: "block_user",
                    success: { (data) -> Void in
                    }, failure:  { (error) -> Void in
                })
        }))

        //Flag Recording
        moreModal.addAction(UIAlertAction(title: "Flag Recording", style: UIAlertActionStyle.default, handler: {(alert: UIAlertAction!) in
            rwf.apiPostAssetsIdVotes(asset_id: assetID, vote_type: "flag",
                success: { (data) -> Void in
                }, failure:  { (error) -> Void in
            })
        }))

        //Cancel
        moreModal.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.default, handler: nil))
        self.present(moreModal, animated: true, completion: nil)

[seeReadCode]

editing this re: https://github.com/seeRead/roundware-ios-digita11y/issues/25 because functionality is covered by the vote method.

---

deprecated Server endpoint is in progress...

Format will be: POST /api/2/blockedcontent/ - with params:

• user - stored in the app already
• asset_id - of asset that is playing on client when the button is pressed
• block_type - “asset” if blocking specific asset only, “user” if blocking all content by user who created asset
• session_id - for tracking purposes