database: Add mod_abs and mod_rel to payment_custom

sql/v01/13.create.payment.sql

@@ -154,8 +154,12 @@ CREATE TABLE payment_custom (
     year        INTEGER NOT NULL,
     mgnr        INTEGER NOT NULL,
 
-    amount  INTEGER NOT NULL,
-    comment TEXT,
+    mod_abs     INTEGER DEFAULT NULL,
+    mod_rel     REAL    DEFAULT NULL,
+    mod_comment TEXT    DEFAULT NULL,
+
+    amount      INTEGER DEFAULT NULL,
+    comment     TEXT    DEFAULT NULL,
 
     CONSTRAINT pk_payment_custom PRIMARY KEY (year, mgnr),
     CONSTRAINT fk_payment_custom_season FOREIGN KEY (year) REFERENCES season (year)

sql/v01/99.schema_version.sql

@@ -1,3 +1,3 @@
 
 -- This value MUST NOT be changed while other connections are open!
-PRAGMA schema_version = 2700;
+PRAGMA schema_version = 2800;