update sell_reason to exit_reason

docs/strategy_migration.md

@@ -25,6 +25,7 @@ You can use the quick summary as checklist. Please refer to the detailed section
   * [`buy_tag` -> `enter_tag` (used for both long and short trades)](#populate_buy_trend)
   * [New column `enter_short` and corresponding new column `exit_short`](#populate_sell_trend)
 * trade-object now has the following new properties: `is_short`, `enter_side`, `exit_side` and `trade_direction`.
+  * `sell_reason` -> `exit_reason`
 * [Renamed `trade.nr_of_successful_buys` to `trade.nr_of_successful_entries` (mostly relevant for `adjust_trade_position()`)](#adjust-trade-position-changes)
 * Introduced new [`leverage` callback](strategy-callbacks.md#leverage-callback).
 * Informative pairs can now pass a 3rd element in the Tuple, defining the candle type.

docs/webhook-config.md

@@ -178,7 +178,7 @@ Possible parameters are:
 * `stake_currency`
 * `base_currency`
 * `fiat_currency`
-* `sell_reason`
+* `exit_reason`
 * `order_type`
 * `open_date`
 * `close_date`
@@ -203,7 +203,7 @@ Possible parameters are:
 * `stake_currency`
 * `base_currency`
 * `fiat_currency`
-* `sell_reason`
+* `exit_reason`
 * `order_type`
 * `open_date`
 * `close_date`
@@ -228,7 +228,7 @@ Possible parameters are:
 * `stake_currency`
 * `base_currency`
 * `fiat_currency`
-* `sell_reason`
+* `exit_reason`
 * `order_type`
 * `open_date`
 * `close_date`