kea-admin lease-upload mysql

Part of #2039 (closed).

upload seems like the best antonym to dump that shows direction.

• a2aa65f7 kea-admin lease-upload mysql
  • This approach tries to do as little work as possible in shell and offload everything as quickly as possible to SQL. Since there is no procedure can accept any input at least not without quotes around it, the only thing kea-admin does is put quotes around values of columns that are varchars or around values that need to be further processed in SQL.
  • This approach does not assume a fixed position of columns in the CSV file, but searches for it every time when it needs to. It only needs to do that when stringifying for the reason above. I don't necessarily want it this way so I can put static columns in there if the reviewer wants. If performance is an issue, you should know that not the ability to dynamically search for columns is not a great burden, but rather the stringification/quoting itself, or the fact that we're not doing batch lease upload, but rather one at a time. I haven't considered batch SQL very much, because I'm not familiar with how portable it is across MySQL versions and how much of a speedup it would bring.
  • dump_type -> dhcp_version because now it's also upload type not only dump type
• f6a9a095 kea-admin lease-upload mysql tests
  • removed some tmp_file references that weren't used anymore
• 2fb4f192 document kea-admin lease-upload
• 5378a406 add ChangeLog entry