Update presto-admin not to remove local connector files on connector remove

[mattsfuller]

A proposal from Brian, though likely without ".properties": Help: presto-admin connector add [connector name | all | all-force] presto-admin connector add Missing parameter: must specify property file name or 'all' or 'all-force' presto-admin connector add hive.properties Copying hive.properties to all nodes ... presto-admin connector add all Preparing to copy all connector configurations to all nodes: hive.properties psql.properties tpch.properties Are you sure? (yes or no) Presto-admin connector add all-force Copying all connector property files to all nodes: hive.properties psql.properties tpch.properties ... If we were to make these changes, then it would be appropriate to not delete the local config file for "connector remove".

[mattsfuller]

Leaving out ".properties" is fine. Also, if the user does not specify a connector, or if they specify one that doesn't exist, we should list the available connectors as part of the error message. presto-admin connector add Missing parameter: must specify existing property file name or 'all' or 'all-force'. Connector property files are stored in /etc/opt/prestoadmin/connectors/. Available connectors are: hive psql tpch presto-admin connector add tpcf Invalid connector name 'tpcf': must specify existing property file name or 'all' or 'all-force'. Connector property files are stored in /etc/opt/prestoadmin/connectors/. Available connectors are: hive psql tpch