getindex not working all the way

[Moelf]

tree[1] or similar with explicit Int works as defined by:

FileTrees.jl/src/datastructure.jl

Line 185 in 43d7baa

Base.getindex(tree::FileTree, i::Int) = tree.children[i]

but tree[end] doesn't work, nor does tree[1:10]. I think we should delegate all of these to tree.children

[shashi]

Good point. Would consider a PR for this!