added mysql.fetch_row_assoc, which returns a table of field names/values

The advantage to the traditional 'fetch_field_row' is that you don't have to know how many columns exist or risk a console error, and that - unrelated to the actual order of the fields - they are always available by name, not by index. This comes especially handy when using 'SELECT * FROM ...'.

Also altered .gitignore to ignore Visual Studio files, and removed them from the repo where appropriate.