Fixes crash with possible negative limit

app/src/main/java/net/pokeranalytics/android/model/migrations/Patcher.kt

@@ -35,6 +35,9 @@ class Patcher {
 			Preferences.executeOnce(Preferences.Keys.PATCH_BLINDS_FORMAT, context) {
 				patchBlindFormat()
 			}
+			Preferences.executeOnce(Preferences.Keys.PATCH_NEGATIVE_LIMITS, context) {
+				patchNegativeLimits()
+			}
 
 			Preferences.executeOnce(Preferences.Keys.ADD_NEW_TRANSACTION_TYPES, context) {
 
@@ -131,6 +134,17 @@ class Patcher {
 			realm.close()
 		}
 
+		private fun patchNegativeLimits() {
+			val realm = Realm.getDefaultInstance()
+			realm.executeTransaction {
+				val sessions = realm.where(Session::class.java).lessThan("limit", 0).findAll()
+				sessions.forEach { session ->
+					session.limit = null
+				}
+			}
+			realm.close()
+		}
+
 		/*
 		02/09/19: A bug with the session set management made them kept instead of deleted,
 		thus making duration calculation wrong

app/src/main/java/net/pokeranalytics/android/model/realm/Session.kt

@@ -271,6 +271,13 @@ open class Session : RealmObject(), Savable, RowUpdatable, RowRepresentable, Tim
 
 	// The limit type: NL, PL...
 	var limit: Int? = null
+		set(value) {
+			field = if (value != null && value >= 0) {
+				value
+			} else {
+				null
+			}
+		}
 
 	// The game played during the Session
 	var game: Game? = null

app/src/main/java/net/pokeranalytics/android/util/Preferences.kt

@@ -42,7 +42,8 @@ class Preferences {
 		LATEST_BLOG_POST_ID_DISPLAYED("latestBlogPostIdDisplayed"),
 		LAST_BLOG_TIPS_RETRIEVAL("lastBlogTipsRetrieval"),
 		SHOW_BLOG_TIPS("showBlogTips"),
-		LAST_REVIEW_REQUEST_DATE("lastReviewRequestDate")
+		LAST_REVIEW_REQUEST_DATE("lastReviewRequestDate"),
+		PATCH_NEGATIVE_LIMITS("negativeLimits")
 	}
 
 	enum class FeedMessage {