Works on Postgres 9.5 and above. Currently restricted because 9.5 is the version that introduced the timestamp creation functions.
These functions will create a range type that spans all the values in the input array.
When the extention is installed, it will create types for all the range types that are in pg_catalog. You can create additional range_from_array() functions by calling _range_from_array__create(range_type)
.