Fixing bitly_get_curl calls that were not using the class method

There were many instances of bitly_get_curl being called still as a global function and not from the class' method.

Most fixes were to make "bitly_get_curl" => "$this->bitly_get_curl"

There is also a fix in the lookup call, so that if the lookup is not found, it skips trying to load in attributes that do not exist, and instead provides and empty array.