Spaces around WHERE clause

This code doesn't typecheck

```
 (<:view< { id=node.id } | node in $nodes_table$; node.id=$int64:nodeId$; >>)
```

but this is OK

```
 (<:view< { id=node.id } | node in $nodes_table$; node.id = $int64:nodeId$; >>)
```

Can allow 1st syntax too?
