* replace asn1 by asn1crypto

* get_node_answer_time added to NodeList
* New node added
* new stored parameter: default_canonical_url
* beempy notifications sorting is reversed, a new parameter can be used to change the sorting
* New beempy createpost command, it can be used to create an empty markdown file with YAML header for a new post
* beempy post has now a canonical_url parameter, when not set, default_canonical_url is set
* New beempy draw command, can be used to generate pseudo random number from block identifiers using hashsums
* remove enum34 dependency

* Fix update_account_jsonmetadata and add posting_json_metadata property to Account
* Add Ledger Nano S support
* beempy -u activates ledger signing
* beempy -u listkeys shows pubkey from ledger
* beempy -u listaccounts searches for accounts that have pubkey derived from attached ledger
* beempy -u keygen creates pubkey lists that can be used for newaccount and changekeys
* new option use_ledger and path for Hive

* add click_shell to turn beempy into a shell utility with autocompletion
* new click_shell added as requirements