Add eip images locally (#2150)

EIPS/eip-747.md

@@ -77,7 +77,7 @@ web3.wallet.watchAsset({
 ```
 Upon calling this request, the user should be prompted with the opportunity to add this token to their wallet:
 
-![ezgif com-video-to-gif](https://user-images.githubusercontent.com/12115171/44558730-2666e300-a71c-11e8-9098-e27ec99b88fb.gif)
+![add-token-prompt 1](../assets/eip-747/add-token-prompt.gif)
 
 For `Base64` images, the user just have to add it as `image` parameter.
 
@@ -95,7 +95,7 @@ web3.wallet.watchAsset({
 ```
 Upon calling this request, the user should be prompted with the opportunity to add this token to their wallet:
 
-![ezgif com-video-to-gif 1](https://user-images.githubusercontent.com/12115171/44558734-2961d380-a71c-11e8-870b-b7d27cfccc87.gif)
+![add-token-prompt 2](../assets/eip-747/add-token-prompt2.gif)
 
 If the user adds this token, it should appear somewhere in their wallet's UI, with its balance, etc.