`Struct#SelectFrom` and `Struct#SelectFromForTag` add table name as prefix to all columns

Per #40, table name should be added as prefix (like table.col) to column names to avoid column name conflict. It's useful when building a SELECT with JOIN.

Add new methods in `Struct` to support INSERT IGNORE INTO and REPLACE INTO

Per #39, add new methods in Struct, including InsertIgnoreInto, ReplaceInto, InsertIgnoreIntoForTag and ReplaceIntoForTag.

New methods to build more complex UPDATE and INSERT INTO

Per #32, add new method SetMore in UpdateBuilder to add more assignments to UPDATE.

Per #33, add new method InsertIgnoreInto in InsertBuilder to support INSERT IGNORE INTO.

New feature: interpolate `args` in the `sql`

#23 This feature is inspired by the interpolation feature implemented by github.com/go-sql-driver/mysql. It's designed to work with some less functional drivers to bind params to a SQL on client side rather than server side.

Add `CreateTableBuilder` and support `REPLACE INTO`

Per #18, add CreateTableBuilder and support REPLACE INTO now.

Per #19, Args#Compile will print raw $ if $ syntax is wrong.