Layout corrections on main iFL tab

[brita-sed]

Precondition

• .../eclipse.exe has launched.
• iFL plugin has been installed.

Steps

1. Select a project.
2. Click iFL button.

Expected results

• The iFL tab will open with the appropriate content.

Received results

• The two buttons are too far from each other, and there is a lot of unnecessary space between the buttons and the widgets.

Environment:

• Package: https://github.com/sed-szeged/iFL4Eclipse/releases/tag/V2.duallist-sorting
• Operating System: Windows 10 Pro, 64 bit
• Eclipse version: 2019-09 R (4.13.0)