Autocompletion on keys with period doesn't work

[weichuliu]

Followed from simeji#54

Tried master version on macOS:

# Initial
[Filter]>
{
  "a.a": "b",
  "c": "d"
}

# pressed ".a"
#           v Cursor 
[Filter]> .a"a.a"]
null

# pressed Tab
#                 v Cursor 
[Filter]> .a"a.a"]
jq: error: syntax error, unexpected QQSTRING_START, expecting $end (Unix shell quoting issues?) at <top-level>, line 1
.a"a.a"]
jq: 1 compile error

jiq kinda recognized the key but failed on autocompletion.