Pagination fix

Problem?
Often times in production we don't want to return all matching records instead returning a paginated response based on values of limit and offset is desirable.

What is being fixed?
Calling .all() will keep returning all records matching the search criterion whereas if you set value of limit and then call .execute() with exhaust_results=False parameter, It will return number of records equal to value of limit.

Usage-
Let us consider 3 scenarios-

Scenario 1

model = Model.find(
    (condition 1) &
    (condition 2) &
    ....
    (condition n)
)
model.limit = 5
model.offset = 0
model.execute(exhaust_results=False)

This will return first 5 records matching search criterion.

Scenario 2

model = Model.find(
    (condition 1) &
    (condition 2) &
    ....
    (condition n)
)
model.execute()

This will return all records matching search criterion.

Scenario 3

model = Model.find(
    (condition 1) &
    (condition 2) &
    ....
    (condition n)
)
model.execute(exhaust_results=False)

This will return top 10 records matching search criterion because default value of limit is 10

How is it fixed?
To break away from loop executing the query a condition is added wherein if total number of fetched records is equal or greater than limit. (see file changes)