Spaces in table, index and field names are actually allowed by SQLite,
so no need to check for them.
However, "`" characters cause problems when appearing in SQL statements
so disallow them instead.

Also update the table view widget and the status message in the Execute
Query tab of the main window when the query was valid but returned no
results.

Fixes #38.

When the user selects multiple lines of SQL code and hits F5 to execute
them the execution stops after the first line because we use the
selectedText() method of the QTextCursor class to get the selected text
and this method returns Unicode U+2029 paragraph separator characters
instead of newline \n characters.
(see http://qt-project.org/doc/qt-4.8/qtextcursor.html#selectedText)
Fix this by replacing these by regular newline characters to.

…identifier

if there was no NL in the line comment we ran into an
endless recursion, now we check for that corner case.

Conflicts:
	src/DbStructureModel.cpp

When called while the Browse Data tab of the main window is selected
also select the current table or view in the ExportCsvDialog.

Sort the table names in the combobox of the ExportCsvDialog.

Conflicts:
	src/ExportCsvDialog.cpp

Clear the tree widget in the 'Database Structure' tab of the main window
after closing a database.
See issue #44.

Reset the recordset label in the Browse Data tab of the main window
after closing a DB file.
See issue #44.

dunno really know whats different here to master branch

DEFAULT also takes quoted literals