migrations: Add 5.sql: Tag support

shared/migrations/5.sql

@@ -0,0 +1,6 @@
+CREATE TABLE tag(id integer PRIMARY KEY, name varchar(128) UNIQUE);
+CREATE TABLE filetag(fileid integer, tagid integer);
+CREATE INDEX filetag_fileid ON filetag(fileid);
+CREATE INDEX tag_id ON tag(id);
+CREATE INDEX file_path ON file ( path );
+UPDATE file SET filetype='c' WHERE filetype='f';

shared/migrations/migrations.qrc

@@ -4,5 +4,6 @@
         <file>2.sql</file>
         <file>3.sql</file>
         <file>4.sql</file>
+        <file>5.sql</file>
     </qresource>
 </RCC>