Allowing InsertColumn method take into account merged cells for multiple
row add columns where the count of cells is less than the index but is
not less table column count

Using AppDomain.CurrentDomain.BaseDirectory instead of Assembly.GetExecutingAssembly().Location to the determine the location of .docx files and other resources. This method is invariant under the test runner in use.
Resources are set to "Copy if newer" to include them during build.