Shifted the png files of eip-823 from root to assets (#1069)

* epi drafted

* minor changes made

* minor changes made

* changes to sender interface and added diagrams

* added diagrams in the markdown

* updated the diagrams

* update the headers

* made changes suggested by @arachnid

* added png to assets folder

EIPS/eip-823.md

@@ -187,13 +187,13 @@ event ExchangeAndSpent ( address _from, address _by, uint _value ,address _targe
 ### Diagramatic Explaination
 
 #### Exchanging Tokens
-![token-exchange-standard-visual-representation-1](https://raw.githubusercontent.com/kashishkhullar/EIPs/master/EIPS/token-exchange-standard-visual-representation-1.PNG)
+![token-exchange-standard-visual-representation-1](https://raw.githubusercontent.com/kashishkhullar/EIPs/master/assets/eip-823/eip-823-token-exchange-standard-visual-representation-1.PNG)
 
 NOTE: After the successful exchange the contract on right owns some tokens of the contract on the left.
 
 #### Exchanging And Spending Tokens
 
-![token-exchange-standard-visual-representation-2](https://raw.githubusercontent.com/kashishkhullar/EIPs/master/EIPS/token-exchange-standard-visual-representation-2.PNG)
+![token-exchange-standard-visual-representation-2](https://raw.githubusercontent.com/kashishkhullar/EIPs/master/assets/eip-823/eip-823-token-exchange-standard-visual-representation-2.PNG)
 
 NOTE: After the successful exchange the contract on right owns some tokens of the contract on the left.