Update sql docs to new schema

Author: xmatthias

docs/sql_cheatsheet.md

@@ -32,9 +32,12 @@ CREATE TABLE trades (
 	exchange VARCHAR NOT NULL,
 	pair VARCHAR NOT NULL,
 	is_open BOOLEAN NOT NULL,
-	fee FLOAT NOT NULL,
+	fee_open FLOAT NOT NULL,
+	fee_close FLOAT NOT NULL,
 	open_rate FLOAT,
+	open_rate_requested FLOAT,
 	close_rate FLOAT,
+	close_rate_requested FLOAT,
 	close_profit FLOAT,
 	stake_amount FLOAT NOT NULL,
 	amount FLOAT,
@@ -71,13 +74,13 @@ WHERE id=31;
 
 ```sql
 INSERT 
-INTO trades (exchange, pair, is_open, fee, open_rate, stake_amount, amount, open_date) 
-VALUES ('BITTREX', 'BTC_<COIN>', 1, 0.0025, <open_rate>, <stake_amount>, <amount>, '<datetime>')
+INTO trades (exchange, pair, is_open, fee_open, fee_close, open_rate, stake_amount, amount, open_date) 
+VALUES ('BITTREX', 'BTC_<COIN>', 1, 0.0025, 0.0025, <open_rate>, <stake_amount>, <amount>, '<datetime>')
 ```
 
 **Example:**
 ```sql
-INSERT INTO trades (exchange, pair, is_open, fee, open_rate, stake_amount, amount, open_date) VALUES ('BITTREX', 'BTC_ETC', 1, 0.0025, 0.00258580, 0.002, 0.7715262081, '2017-11-28 12:44:24.000000')
+INSERT INTO trades (exchange, pair, is_open, fee_open, fee_close, open_rate, stake_amount, amount, open_date) VALUES ('BITTREX', 'BTC_ETC', 1, 0.0025, 0.0025, 0.00258580, 0.002, 0.7715262081, '2017-11-28 12:44:24.000000')
 ```
 
 ## Fix wrong fees in the table
@@ -87,4 +90,4 @@ If your DB was created before
 
 ```sql
 UPDATE trades SET fee=0.0025 WHERE fee=0.005;
-```
+```