Add _version queries

Author: antweb

libpretixsync/src/main/sqldelight/common/eu/pretix/libpretixsync/sqldelight/_version.sq

@@ -0,0 +1,14 @@
+selectVersion:
+SELECT version
+FROM _version
+LIMIT 1;
+
+deleteVersion:
+DELETE FROM _version;
+
+insertVersion:
+INSERT INTO _version (
+    version
+) VALUES (
+    ?
+);

libpretixsync/src/main/sqldelight/postgres/eu/pretix/libpretixsync/sqldelight/_version.sq

@@ -0,0 +1,3 @@
+CREATE TABLE _version (
+    version numeric
+);

libpretixsync/src/main/sqldelight/sqlite/eu/pretix/libpretixsync/sqldelight/_version.sq

@@ -0,0 +1,3 @@
+CREATE TABLE _version (
+    version INTEGER
+);