add unicode superscripts and subscripts to latex substitutions
replace \\Elzxh with \\hbar to match latex usage
moved super/subscripts and hbar to manually added section
get rid of curly braces in latex super/subscripts and add \del mapping
Merge branch 'master' into sub_super
fix #6672 (better reducedim type inference)
tweaks of the sum functions.

Introduce subzero, add zero, etc to enhance consistency & efficiency.
merge three sum{T}(a::AbstractArray{T) for different kinds of T into a single method
specialize of sum(x) when x is a number
Merge pull request #6927 from lstagner/sub_super

add unicode superscripts and subscripts to latex substitutions
minor fix of addzero(::AbstractArray)
julia-mode LaTeX symbol-table update
make `sum(x::Number) = x`
Merge pull request #7013 from lindahua/dh/sum2

Tweaks of sum functions
Merge pull request #6994 from stevengj/reducedim_type

better reducedim type inference
fix #7012, :: on array assignment LHS
Merge branch 'master' of github.com:JuliaLang/julia