Change ticker interval from minutes as integer to string (1m, 5m, 1h,...)

docs/backtesting.md

@@ -33,7 +33,7 @@ python3 ./freqtrade/main.py backtesting --realistic-simulation
 
 **With 1 min tickers**
 ```bash
-python3 ./freqtrade/main.py backtesting --realistic-simulation --ticker-interval 1
+python3 ./freqtrade/main.py backtesting --realistic-simulation --ticker-interval 1m
 ```
 
 **Reload your testdata files**

docs/bot-usage.md

@@ -118,7 +118,7 @@ optional arguments:
   -h, --help            show this help message and exit
   -l, --live            using live data
   -i INT, --ticker-interval INT
-                        specify ticker interval in minutes (default: 5)
+                        specify ticker interval (default: '5m')
   --realistic-simulation
                         uses max_open_trades from config to simulate real
                         world limitations

docs/configuration.md

@@ -17,7 +17,7 @@ The table below will list all configuration parameters.
 | `max_open_trades` | 3 | Yes | Number of trades open your bot will have.
 | `stake_currency` | BTC | Yes | Crypto-currency used for trading.
 | `stake_amount` | 0.05 | Yes | Amount of crypto-currency your bot will use for each trade. Per default, the bot will use (0.05 BTC x 3) = 0.15 BTC in total will be always engaged.
-| `ticker_interval` | [1, 5, 30, 60, 1440] | No | The ticker interval to use (1min, 5 min, 30 min, 1 hour or 1 day). Defaut is 5 minutes
+| `ticker_interval` | [1m, 5m, 30m, 1h, 1d] | No | The ticker interval to use (1min, 5 min, 30 min, 1 hour or 1 day). Default is 5 minutes
 | `fiat_display_currency` | USD | Yes | Fiat currency used to show your profits. More information below. 
 | `dry_run` | true | Yes | Define if the bot must be in Dry-run or production mode. 
 | `minimal_roi` | See below | No | Set the threshold in percent the bot will use to sell a trade. More information below. If set, this parameter will override `minimal_roi` from your strategy file.