changes to property names making it json friendly

Author: kartikbb

README.md

@@ -47,7 +47,7 @@ The `identify` lets you tie a user to their actions and record traits about them
 Example `user` call:
 ```
 track.user(
-	user_id="<user_id in your db>",
+	userId="<user_id in your db>",
 	traits={
 		"name": "John Doe",
 		"email": "john@email.com",
@@ -58,15 +58,15 @@ track.user(
 #### The `user` call has the following fields:
 |Field|Data type|Description|
 |--|--|--|
-|user_id|str or int|The ID for the user in your database.|
-|country_code|str|country code for the phone_number (default value is "+91")|
-|phone_number|str|phone_number without country_code (eg: "9876598765")|
+|userId|str or int|The ID for the user in your database.|
+|countryCode|str|country code for the phone_number (default value is "+91")|
+|phoneNumber|str|phone_number without country_code (eg: "9876598765")|
 |traits|dict|A dict of traits you know about the user. Things like: `email`, `name` or `age`|
 
 **NOTE:** Atleast one of these two is required for user identification :
 
- - **user_id**, OR
- - **phone_number** with **country_code**
+ - **userId**, OR
+ - **phoneNumber** with **countryCode**
 
 
 
@@ -76,7 +76,7 @@ track.user(
 Example `event` call:
 ```
 track.event(
-	user_id="<user_id in your db>",
+	userId="<user id in your db>",
 	event="Product Added",
 	traits={"price": 200}
 )
@@ -85,6 +85,6 @@ track.event(
 
 |Field|Data type|Description|
 |--|--|--|
-|user_id|str or int|The ID for the user in your database.|
+|userId|str or int|The ID for the user in your database.|
 |event|str|Name of the event you want to track, For eg: "Product Added".|
 |traits|dict|dictionary of properties for the event. If the event was **Product Added**, it might have properties like `price` or `product_name`.|