Documentation for constructor needed

[loginov-rocks]

Hello and thank you for a great solution at first!

So. If we take a look at the contructor of meArm class, we can't understand what values possible for angles' limits. For example, I faced with an issue when using default constructors' min and max values for angles, especially for the elbow servo. If I use pi/4 for the angleMinShoulder, meArm wouldn't move as expected, vertical movement is not vertical :)

In an explanatory article http://bitofahack.com/post/1433701488 angleMinShoulder set to 0, I used it and it helped. So can we have may be another .md file where all of this will be explained?

P.S.: I use Me Arm version 0.4.