dynect: dns: dramatically improve speed of 'get_all_records' request and 'records.all' method.

previously 4 minutes on a domain with many records, now around 5 seconds
this is enabled by a parameter to the 'get_all_records' request, detail=y, which returns full records, rather than resource URLs.
Merge pull request #3023 from shawncatz/dynect_all_records

[dynect|dns] dramatically improve speed ...