[#205] New custom schema for redis index

[eddiebrissow]

closes #205

QE constructor now accepts pattern_index_templates option:

1. User don't starts QE with pattern_index_templates option -> Loads custom templates from DB
2. User starts QE with pattern_index_templates option -> Loads from DB, if the pattern_index_templates is different from loaded, ERROR
3. User don't starts QE with pattern_index_templates option and fresh DB -> save default pattern_index_templates

Custom templates example (pattern_index_templates):

 [{
            "field":  "named_type",
            "value": "Similarity"
            "positions": [0,1],
            "arity": 2
            },
             {
            "field":  "targets[0]",
            "value": "b5459e299a5c5e8662c427f7e01b3bf1"
            "positions": [1,2]
            "arity": 3
            },
          {
            "field":  "targets[0]",
            "value": "c1db9b517073e51eb7ef6fed608ec204"
            "positions": [0,2,4,8]
            "arity": 10
            }
            
]

[andre-senna]

Before merging this PR, I think we need an integration test case where we test which pattern keys are actually being generated IN THE REDIS TABLE given a custom index spec.

For instance if we use this spec:

[{
            "field":  "targets[0]",
            "value": hasher.terminal_hash("Symbol", "Similarity")
            "positions": [1,2]
            "arity": 3
            },         
]

And add this expression:

(Similarity "Human" "Monkey")

I want to see the patterns actually added to the PATTERNS index in such a way that we can retrieve this expression if we make any of these queries:

(Similarity * "Monkey")
(Similarity "Human" *)
(Similarity * *)

Of course we want to vary the spec and the query format in several different cases.

[eddiebrissow]

Before merging this PR, I think we need an integration test case where we test which pattern keys are actually being generated IN THE REDIS TABLE given a custom index spec.

For instance if we use this spec:

[{
            "field":  "targets[0]",
            "value": hasher.terminal_hash("Symbol", "Similarity")
            "positions": [1,2]
            "arity": 3
            },         
]

And add this expression:

(Similarity "Human" "Monkey")

I want to see the patterns actually added to the PATTERNS index in such a way that we can retrieve this expression if we make any of these queries:

(Similarity * "Monkey")
(Similarity "Human" *)
(Similarity * *)

Of course we want to vary the spec and the query format in several different cases.

Before merging this PR, I think we need an integration test case where we test which pattern keys are actually being generated IN THE REDIS TABLE given a custom index spec.

For instance if we use this spec:

[{
            "field":  "targets[0]",
            "value": hasher.terminal_hash("Symbol", "Similarity")
            "positions": [1,2]
            "arity": 3
            },         
]

And add this expression:

(Similarity "Human" "Monkey")

I want to see the patterns actually added to the PATTERNS index in such a way that we can retrieve this expression if we make any of these queries:

(Similarity * "Monkey")
(Similarity "Human" *)
(Similarity * *)

Of course we want to vary the spec and the query format in several different cases.

Added more tests