Merge pull request #34 from markiewb/master

Fix issue #9 - Add support context menu for folder and project nodes
issue #35: Issues with Dark LAFs (f.e. Dark Metal)

[ui] updated custom forms/options to be compatible to dark themes
introduced in NB74 (labels use correct colors, tooltips use link color,
all tables use default colors, buttons have size height, ...)
[ui] redesign of optionpanel - resizes correctly now
issue #38 - java.lang.IndexOutOfBoundsException when clicking on any empty table in the plugin

[fix] add check for valid row index
Merge pull request #37 from markiewb/bugfix/fix_35

issue #35: Issues with Dark LAFs (f.e. Dark Metal)
Merge pull request #39 from markiewb/bugfix/fix_38

issue #38 - java.lang.IndexOutOfBoundsException when clicking on any empty table in the plugin
built against nb 7.4