Let user set point data type

[NubeDev]

Let user set point type

• string
• float
• int

[RaiBnod]

It should be only for generic point.

[RaiBnod]

@NubeDev while we use the point data type as string, we need to change on followings:

On point_store and point_store_history tables:

• value from float to string (we store 1 as "1", "value" as "value", "20.12" as "20.12")
• value_original float to string

& also on InfluxDB we will store value as string previously it was storing as float.

Moreover, our priority_array array fields values are also float, they needs to convert it on string.

Please confirm on it before proceeding the changes.

[Shiny380]

Related #80
This is a major change and should be left until later after better discussion
More important issues to be worked on atm

[RaiBnod]

After discussion, we are adding generic_point > type and if type=string we are storing value_raw as string value leaving value as null aside.