#1 tree layout

[Luka Napotnik]

user can choose between different tree layouts. For
example:

1) two horinzotal trees
+--------+---------+
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+--------+---------+

2) two horizontal, one buttom-vertical
+--------+---------+
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+--------+---------+
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+--------+---------+

3) two horizontal, one top-tvertical
+------------------+
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+--------+---------+
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+--------+---------+