This fixes a small issue in src/widgets.zsh which makes it so if you
alias [ to g[ (as is done in prezto if the gnu-utility module is loaded)
autosuggestions would fail.

The documentation for GNU test mentions that -o and -a should be avoided
if possible because it's not very clear. Also, with zsh and [[ -o
actually tests if an option is set, which makes this option even more
confusing.

Seems like this would happen on some machines but not on others. Not
sure exactly what's going on, but this is such an edge case I'm just
going to remove the test.

Github #247 and #258

While they are still experimental

[GitHub #219]

Intended to be helpful for folks using bracketed-paste-magic and other
widgets that use `zle -U`.

Depends on patch to ZSH from workers/40702:

  http://www.zsh.org/mla/workers/2017/msg00414.html

Puts in a better fix for #126 and related issues.

Can attach while tests are stopped with `tmux -L <socket_name> attach`

Fixes flaky test

Prevents some flakiness in tests

As far as I know, `fc` makes it impossible to tell whether history items
used an actual newline character or the string "\n". Pulling from the
`$history` array gives a more accurate representation of the actual
command that was run.