Add extract alfanumeric with selected special characters

add commonly used special characters to be included with alfa numeric extraction from a string.
allowed special characters are !"#$%&'()*+,-./ \[]\n

v0.0.2: Add case in switch statement for handling map type (#3)

* Add map type on assign function

* Add casting time.duration to int64

Initial release with basic functions

Initial codes supporting array/slice, object, and string processing.