Bizarre behavior of Julia display()

Running the following Julia code creates some bizarre output. It appears that `display()` runs much faster than the other functions and the resulting table shows up before you want it to. It can even show up in the middle of other tables that are output with the other methods.

Even if there is a work around, I don't think this should behave this way. Output should be displayed in the order it was inputted.

```
using DataFrames
A = DataFrame(randn(10, 7));

print("\n\n\n", "A = DataFrame(randn(10, 7))")

print("\n\n\n","print(A)\n")
print(A)

print("\n\n\n","show(A)\n")
show(A)

print("\n\n\n","show(A, true)\n")
show(A, true)

print("\n\n\n","show(A, false)\n")
show(A, false)

print("\n\n\n","showall(A)\n")
showall(A)

print("\n\n\n","showall(A, true)\n")
showall(A, true)

print("\n\n\n","showall(A, false)\n")
showall(A, false)

print("\n\n\n","display(A)\n")
display(A)
```

Start by running the Julia DataFrames reproduction in a Jupyter notebook and compare the ordering of print(), show(), showall(), and display() output. Trace how notebook outputs from display() are submitted and rendered, then verify that the reproduced output appears in the same order as the input calls.

Written by the indexing model from the issue text.