Improve copying/move variables between CMake configurations

Hello! I think that it is inconvenient to fill almost the same variables in different CMake configurations.

For example, I'd like to copy-paste several variable-value pairs from Release to RelWithDebInfo.

I'd like to have an "import tableview".  The left table is the current table with CMake variables. The right table contains variables from another CMake configuration (config can be chosen via combobox on the top of the right table). I can multiselect rows from the right table and copy them by clicking on the "arrow" button "<=".

It is even interesting to make bidirectional copy (or move) between two tables. So, more buttons required.

BTW, double-clicking on the cell with variable name in the left table can show embedded combobox with saved variable names from all configuratons (for autocomplete).