Client-server protocol description update

server/protocol.txt

@@ -2,8 +2,13 @@ Description: Sent when client opens Downloader
 Request: ID, CountriesV, PurchasesV
 {
   "ID":"12345",                   // unique client id
-  "CountriesVersion":1,
-  "PurchasesVersion":1
+  "Cmd":"VersionCheck",
+  "Params":
+  {
+    "CountriesV":1,               // local version of countries file on the client
+    "PurchasesV":1,               // local version of purchases file on the client
+    "ClientV":1                   // client version
+  }
 }
 Response: Credit [, CountriesV, Countries, PurchasesV, Purchases]
 {
@@ -11,14 +16,18 @@ Response: Credit [, CountriesV, Countries, PurchasesV, Purchases]
   "CountriesV":2,                 // optional, latest version of countries list
   "Countries":{...},              // optional, latest countries list with new prices and new countries
   "PurchasesV":2,                 // optional, latest inapp purchases list version
-  "StoreIDS":["123","456","789"]  // optional, latest inapp purchases IDS
+  "Purchases":["123","456","789"]  // optional, latest inapp purchases IDS
 }
 
 Description: Sent by client to validate payment and add credits
 Request: ID, Receipt
 {
   "ID":"12345",
-  "Receipt":"ASD24@#$!@$%"        // base 64 encoded app store receipt to validate and store on our server
+  "Cmd":"ValidatePayment",
+  "Params":
+  {
+    "Receipt":"ASD24@#$!@$%"        // base 64 encoded app store receipt to validate and store on our server
+  }
 }
 Response: Credit [, Error]
 {
@@ -27,10 +36,14 @@ Response: Credit [, Error]
 }
 
 Description: Sent by client to add some credit by entering friend promo code or any other public promo code
-Request: ID, PromoCode
+Request: ID, Code
 {
   "ID":"12345",
-  "PromoCode":"123asdREWR24ad"
+  "Cmd":"ValidatePromoCode",
+  "Params":
+  {
+    "Code":"123asdREWR24ad"
+  }
 }
 Response: Credit [, Error]
 {
@@ -42,7 +55,11 @@ Description: Sent by client when he tries to download the country
 Request: ID, Country
 {
   "ID":"12345",
-  "Country":"Belarus"
+  "Cmd":"Download",
+  "Params":
+  {
+    "Country":"Belarus"
+  }
 }
 Response: Country[, Url | Error]
 {
@@ -55,7 +72,7 @@ Description: Client requests own "Bring friend" code once, which should be enter
 Request: ID, FriendCode
 {
   "ID":"12345",
-  "FriendCode":""
+  "Cmd":"FriendCode",
 }
 Response: FriendCode
 {