Castep band structure path analyser cannot parse 'break' keyword

[azanre]

In castep the 'break' keyword can be used to specify a jump from one point in k space to another when providing a band structure path. This causes an error in the sumo special k point label finder as the line structure cannot be separated into a tuple of k space coordinates. A simple workaround would be to check if a line in the k point path contains 'break' and ignore such lines.