straighten up corners of a line

Hello, 

I have this path that meanders generally moves in either straight lines. However, when a corner is made, there is either a point in the middle with a 45 or -45 angle or some blurp that comes off the lines. I was wondering if there was an easy way to fix these points to straighten these segements of the line (or in the case ofthe corners, to have sharp corners)? I linked the data

Thank you

Andrew