Oscar Benjamin

This came up recently on the [mailing list](https://groups.google.com/forum/#!topic/sympy/x80-mTsXQx8). I think it would be reasonable to change from Easy-to-fix to Good-first-issue except that it's difficult to get everyone to understand a...

The summation gives a Piecewise: ```python In [57]: summation(exp(1+(2*i)/n),(i,1,n)) Out[57]: ⎛⎧ 2 ⎞ ⎜⎪ ─ ⎟ ⎜⎪ n ⎟ ⎜⎪ n for ℯ = 1⎟ ⎜⎪ ⎟ ⎜⎪ 2 2⋅(n...

It would have to be backported to the 1.14 branch. I think there was another but that was worth making a release over so I was intending to do that...

This is not really a bugfix and there are too many changes. I don't think that it makes sense for this to be backported.