Columns width should be based on data as well as column names

Three related bugs/feature requests:

How to reproduce:

1. Open the Query Tool window.
2. Enter "SELECT 'longer text than the title' AS shorter_title" in the
query window.
3. Run the query.

Result: The width of the column in the Data Output tab fits the string
"shorter_title", but the result cell is cut off after "longer t"
(depends on the font).

Expected: The width should fit the widest of either the column name
("shorter_title"), data type ("unknown"), or any rows ("longer text
than the title").

4. Drag the right of the column frame to change the column width.
5. Double-click the column frame to auto-fit the width.

This also resizes the width to fit the column name or data type,
rather than the longest string in the column. In addition, unless the
column border bisects a visible character, it's not really visible
whether there is any more data in the column. This could be indicated
by for example fading out the text at the right edge of the column.
Only if there really is hidden data, though. I've seen implementations
of this which would shade the right side even though the width exactly
fit the data.

Of course, there might be a slight performance issue here, and some
column data might be very wide, so here are some quick suggestions for
a more usable compromise:
* Only check the first N rows for the max width (plus the column name
and data type, as before).
* Implement some restrictions if it turns out that the width of all
the output will be wider than the window. For example, set a maximum
width, or reduce the widest column widths until they all fit.
* Resize to the widest data in *all* the fetched rows if the user
double-clicks the right column border; I usually assume that manual
intervention means the user *really* wants to see the full width.

OS: Ubuntu 12.04.1
pgAdmin 1.14.0

-- 
Cheers
V