Simplify does not pull out common factors from polynomials

[ndinsmore]

Simplify seems to be struggling with basic polynomial common factor extraction. It in fact seems to favor the expanded form of a factorpolynomial ie `2(a+b)"simplifies" to2a+2b`.

julia> using Symbolics

julia> @syms a b c
(a, b, c)

julia> simplify(2*(a+b) )
2a + 2b

julia> simplify(2*(1+a+a^2+a^3+a^4+a^5))
2 + 2a + 2(a^2) + 2(a^3) + 2(a^4) + 2(a^5)

julia> simplify( a / (b + c) + a / (b + c)^2 )
(a + a*b + a*c) / ((b + c)^2) 

I understand that sometimes the expanded form is needed for other simplifications to be investigated, but you would expect that once no further simplifications are found in that search tree it reverts to non-expanded form.

[ndinsmore]

I meant to put this in symbolics.jl