Eeschema: fixed some issues in undo/redo and ESC commands related to hierarchical sheets; Work in progress

Grid list display in popup menu: go back to the previous version, due to problems when using tabs in this menu.

fixed very minor bugs.

Build BOM: in one part per line, fields are now selectable (like others formats)

* Some bugs fixed
* Starting enhancements in Libedit: menubar and commands to "plot" current component in PNG or SVF file (SVG file not fully working, must be refined)

output 8 user fields

* Replaced find dialog with wxFormBuilder version.
* New find dialog is modeless, supports more advanced search features,
  remembers it's last position, size, search history, and search settings,
  and implements initial support for replacing.
* Added Shift+F5 hot key to search for next DRC marker.  F5 now just
  repeats previous search.
* Minor cosmetic enhancements to label edit dialog.
* Remove tab from grid size text printf to fix toolbar grid combobox
  display in wxGTK.
* Updated my TODO list items.

German translation update. Replaced dialog page settings dialogblock version by the same built with wxFormBuilder

Updated Polish translation from new member of Polish Kicad Team: Paweł Dras <dexx.electronic@gmail.com>
Thanks!