Results do not match other implementations

The following queries provide results that do not match those of other implementations of JSONPath (compare https://cburgmer.github.io/json-path-comparison/):

[x] $[1:3] Input:

{":": 42, "more": "string", "a": 1, "b": 2, "c": 3}

Expected output:

[]

Error:

** (Poison.EncodeError) unable to encode value: {"b", 2}
  lib/poison/encoder.ex:383: Poison.Encoder.Any.encode/2
  lib/poison/encoder.ex:259: anonymous fn/3 in Poison.Encoder.List.encode/3
  lib/poison/encoder.ex:260: Poison.Encoder.List."-encode/3-lists^foldr/2-1-"/3
  lib/poison/encoder.ex:260: Poison.Encoder.List.encode/3
  lib/poison.ex:41: Poison.encode!/2
  lib/jsonpath.ex:8: Mix.Tasks.Execute.run/1

[x] $[0:0] Input:
```
["first", "second"]
```
Expected output:
```
[]
```
Actual output:
```
["first", "second"]
```

[ ] $[-4:] Input:

["first", "second", "third"]

Expected output:

["first", "second", "third"]

Actual output:

[]

[x] $..[0] Input:

["first", {"key": ["first nested", {"more": [{"nested": ["deepest", "second"]}, ["more", "values"]]}]}]

Expected output (in any order as no consensus on ordering exists):

["deepest", "first nested", "first", "more", {"nested": ["deepest", "second"]}]

Error:

** (MatchError) no match of right hand side value: {:error, %ExJSONPath.ParsingError{message: "syntax error before: '['"}}
  lib/jsonpath.ex:7: Mix.Tasks.Execute.run/1

[ ] $[*] Input:

["string", 42, {"key": "value"}, [0, 1]]

Expected output:

["string", 42, {"key": "value"}, [0, 1]]

Error:

** (MatchError) no match of right hand side value: {:error, %ExJSONPath.ParsingError{message: "syntax error before: '*'"}}
  lib/jsonpath.ex:7: Mix.Tasks.Execute.run/1

[ ] $.key-dash Input:

{"key-dash": "value"}

Expected output:

["value"]

Error:

** (MatchError) no match of right hand side value: {:error, %ExJSONPath.ParsingError{message: "illegal characters \"-d\""}}
  lib/jsonpath.ex:7: Mix.Tasks.Execute.run/1

[ ] $.屬性 Input:

{"\u5c6c\u6027": "value"}

Expected output:

["value"]

Error:

** (MatchError) no match of right hand side value: {:error, %ExJSONPath.ParsingError{message: "illegal characters \"屬\""}}
  lib/jsonpath.ex:7: Mix.Tasks.Execute.run/1

[ ] $.2 Input:

{"a": "first", "2": "second", "b": "third"}

Expected output:

["second"]

Actual output:

[]

[ ] $..* Input:

{"key": "value", "another key": {"complex": "string", "primitives": [0, 1]}}

Expected output (in any order as no consensus on ordering exists):

["string", "value", 0, 1, [0, 1], {"complex": "string", "primitives": [0, 1]}]

Error:

** (MatchError) no match of right hand side value: {:error, %ExJSONPath.ParsingError{message: "syntax error before: '*'"}}
  lib/jsonpath.ex:7: Mix.Tasks.Execute.run/1

[x] $ Input:

{"key": "value", "another key": {"complex": ["a", 1]}}

Expected output:

[{"another key": {"complex": ["a", 1]}, "key": "value"}]

Error:

** (MatchError) no match of right hand side value: {:error, %ExJSONPath.ParsingError{message: "syntax error before: "}}
  lib/jsonpath.ex:7: Mix.Tasks.Execute.run/1

For reference, the output was generated by the program in https://github.com/cburgmer/json-path-comparison/tree/master/implementations/Elixir_ExJsonPath.

secomind / exjsonpath

Results do not match other implementations #20