Silo graphs and bug fixes — Steam Revolution: The Age of Rail Steam update #47433

Added ability to show graph for storage silos. This required having a generalized graph dialog instead of being part of the industry. Now clicking the graph button will pop up a new dialog with the graph. This comes with a minor slowdown at the simulation speed at all times. This is because now I need to generate the graph data for the silos also. But this should be quite cheap. I was incorrectly generating errors for tracks that were straight in 2D but had high curvature up or down as having too high of a curvature. Instead I should have been checking the 2D curvature instead of the 3D curvature. I was also failing to detect when slopes were too steep. This is because I used to have only the absolute value of the slope. However, I changed the physics to use signed slopes, but didn't update my error checking code. Fixed quest text that was incorrectly referring to the player's gender whe...