PR# 11209 Improve string display for readability in the debugger

I'd like to suggest the following changes to the way text strings are displayed and handled in the debugger.

1) Change the default upper limit for string lengths to something like 250 or more. The current default of 50 is never adequate, and is ridiculous when you consider that I need a machine with at least 2 GB of RAM to be able to even compile my project, much less debug it.

2) Okay, so clicking on the text 'Value' field turns this into a deceptive text edit widget where the text can't be edited. I've learned to live with that or at least put it in some other problem report. But at least the whole text string could be placed into the widget, so long as its relatively small (say 20K). Right now it gets truncated at the default length of 59.

3) There's no need to quote the displayed strings, since it's in its old text grid. This is probably a hangover from the older display that didn't use a tree grid.

4) When the internal_native_array is opened, I would strongly recommend changing how this data gets displayed. Ideally, create two (or even three) subcolumns of character, hex and decimal values for the text entries. Again, there would be no need to quote the character value, since this just makes the text harder to read. Alternatively, a formatted display of the form 
    | a  97 0x51 | 
would be more readable (where '|' indicates the edges of the text field displaying the values). I don't think there's any need to quote the decimal value in slashes either. Again, this just makes the text that much harder to read in the display.

Also, changing the default display length for strings during a debug session doesn't appear to go into effect immediately. It would be nice if the change was immediate, since making this change is often being done at the time it's needed.

Thank you for those suggestions.

- For now we changed the way we display CHARACTER and WIDE_CHARACTER
instead of displaying  / 97 / : 'a'  we now display  97 'a'
which is easier to read (less text polluting the information).

- We decided to have either the decimal or the hexdecimal format, but not both at the same time to make it easier to read.
 If you want to have the hexadecimal value, please use the [0x] button to switch from decimal to hexadecimal format.

- For now we decided to keep the double quotes when displaying STRING value. Since the string may contain some %T and %N character displayed as "%T" and "%N" string, we prefer to keep the double quote as any manifest string. However this decision is not final and may change in the future.

- To display more than 50 characters for a specific string, we advice you to use the Expanded display tool which allow you to specify the lower and upper limits, or to display the full string. (You can use the shortcut Ctrl+E to quickly open this tool on
....
Output truncated, Click download to get the full message