LibSQL+SQLServer: Implement first cut of SELECT ... ORDER BY foo

Ordering is done by replacing the straight Vector holding the query
result in the SQLResult object with a dedicated Vector subclass that
inserts result rows according to their sort key using a binary search.
This is done in the ResultSet class.

There are limitations:
- "SELECT ... ORDER BY 1" (or 2 or 3 etc) is supposed to sort by the
n-th result column. This doesn't work yet
- "SELECT ... column-expression alias ... ORDER BY alias" is supposed to
sort by the column with the given alias. This doesn't work yet

What does work however is something like
```SELECT foo FROM bar SORT BY quux```
i.e. sorted by a column not in the result set. Once functions are
supported it should be possible to sort by random functions.

Userland/Libraries/LibSQL/CMakeLists.txt

@@ -17,6 +17,7 @@ set(SOURCES
     Index.cpp
     Key.cpp
     Meta.cpp
+    ResultSet.cpp
     Row.cpp
     Serializer.cpp
     SQLClient.cpp