Fix syntax errors in `t`

[danporterhonor]

Fixes the following syntax errors I was getting:

.../bin/t: line 142: conditional binary operator expected
.../bin/t: line 142: syntax error near `$FZF_TMUX_OPTS'
.../bin/t: line 142: `      if [[ ! -v $FZF_TMUX_OPTS ]]; then'

and

.../bin/t: line 235: syntax error near unexpected token `;'
.../bin/t: line 235: `  detached) ;&'

[joshmedeski]

The plugin works as-is with bash v4, but I realize most people's computers ship with bash v3.

Let me do some testing and make sure everything is good, I'd also like to keep the same indentation as before if we decide to merge these changes.

[danporterhonor]

The plugin works as-is with bash v4, but I realize most people's computers ship with bash v3.

Let me do some testing and make sure everything is good, I'd also like to keep the same indentation as before if we decide to merge these changes.

I'll fix the indentation.

[danporterhonor]

The plugin works as-is with bash v4, but I realize most people's computers ship with bash v3.

Let me do some testing and make sure everything is good, I'd also like to keep the same indentation as before if we decide to merge these changes.

@joshmedeski converted my spaces into tabs and fixed up a couple other inadvertent changes I made.

[joshmedeski]

Closing in favor of #85

Thanks for the work!