fix memory leak
Allow space characters in table and index names, disallow ` chars

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.
MainWindow: Update execute query table view when no results returned

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.
SqlExecutionArea: Replace UTF8 paragraph separator by newline char

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.
Fix lexer to allow a lot more unicode characters in column and table identifier
remove merge artifact
push version