2284_series: Rectified the limit(( 1.0*1 + 1.0*x)**( 1.0*1/x))

-> This is a fix to the bug reported in issue 2284.

https://code.google.com/p/sympy/issues/detail?id=2284&q=label%3ASeries&sort=summary%20-id&colspec=ID%20Type%20Status%20Priority%20Milestone%20Reporter%20Summary%20Stars

-> The output of the limit was oo(wrong) earlier which should be E but now output is 2.71828182845905 (E).
-> The error is due to the presence of terms like 1.0/3 in taylor series which evaluate to 0.33333.
-> So the fix adopted is to convert these terms to Rational Numbers and then evaluate.