Avoid exception when no tags provided during data upload

If no tags are provided during data upload it fails with a null
exception on splitting the string. If tags is null force it to be empty
string.
Preserve selected project when searching for map

When searching for a published map multiple times maintain the same
selected project across displays of the dialog. Holds last selected
project name on tool. Dialog's selected project now settable.
Reselecting by project id rather than by name

When searching for map and preserving project, make sure we reselect
based on id rather than name.