[FEA]JSON reader: support "allowBackslashEscapingAnyCharacter"

[GaryShen2008]

From the Spark JSON option,
allowBackslashEscapingAnyCharacter
Allows accepting quoting of all character using backslash quoting mechanism.

typically only a few chars in the JSON standard are allowed.
In CUDF they only support ", , \t, \r, and \b. Not sure if there are others in JSON or not. Also not sure what happens if CUDF if others are encountered vs in Spark.

We need to figure out the set of characters which should be supported.

Because of how cuda works it is very rare for CUDF to return an error if it sees an escape it does not understand. We are likely just going to have to document the differences.

[nartal1]

Spark supports these escape characters : \", \, \/, \b, \f, \n, \r, \t, \uXXXX.
CUDF supports these for now: \", \, \t, \r and \b.
Other than these, when allowBackslashEscapingAnyCharacter option is set to true in Spark, any character can be escaped. For example: \$10 results to $10.

Currently CUDF doesn't throw error for the escape characters which are not supported. Output would be same as input.
Example: \nabc results to \nabc.

[nartal1]

I think falling back to CPU when this option is set is the right way for now.
allowBackslashEscapingAnyCharacter is boolean so we cannot partially support only those escape characters which are supported by CUDF.
So we can enable this only when other escape characters are supported(\n , \uXXXX etc) along with supporting escaping backslash for any other characters.

[revans2]

Note that this is related to #10596

[revans2]

Also I just tested and \uXXXX appears to work properly out of the box with CUDF.