pgAdmin 4 commit: Fixed review comments for Import/Export Servers.

Fixed review comments for Import/Export Servers.

refs #4803

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=8b13f158ababee3d860414e39381cfced2e0ecd5

Modified Files
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.../images/import_export_servers_refresh_tree.png  | Bin 42683 -> 0 bytes
docs/en_US/images/import_export_servers_step1.png  | Bin 81277 -> 106802 bytes
docs/en_US/images/import_export_servers_step3.png  | Bin 82423 -> 103500 bytes
docs/en_US/import_export_servers.rst               |  16 +--
web/pgadmin/misc/file_manager/static/js/utility.js |   2 +-
.../file_manager/templates/file_manager/index.html |   2 +-
.../tools/import_export_servers/__init__.py        |  15 ++-
.../static/js/ImportExportServers.jsx              | 123 +++++++++++----------
.../static/js/import_export_selection.ui.js        |   3 +-
web/pgadmin/utils/__init__.py                      |  32 +++---
10 files changed, 103 insertions(+), 90 deletions(-)