* fix wxWidgets asserts

TarArchive::isTarArchive() and SPDCDataFormat::isThisFormat() no longer cause
src/common/string.cpp(1187): assert "c < 0x80" failed in FromAscii(): Non-ASCII value passed to FromAscii().

MainWindow::~MainWindow() and MapEditorWindow::~MapEditorWindow() no longer cause
src/common/wincmn.cpp(468): assert "GetEventHandler() == this" failed in ~wxWindowBase(): any pushed event handlers must have been removed
Merge pull request #47 from alexey-lysiuk/assert_fixes

Fixes for wxWidgets asserts
Initial work
Initial implementation of object edit feature, default key 'e'. Still need to do rotation and merging/splitting when done, possibly an interface for specifying offset/scale/rotation manually also
Holding shift during object edit now disables grid snap
Add ObjectEdit.h
Object edit hilighted line/sector if no selection present
Rearranged the texture editor layout somewhat to help everthing fit properly on smaller screens (TEXTURES especially)
Potential fix for crash on selecting a context menu item in the texture list
No need to remove the archive .bak file before copying, wxCopyFile will overwrite the file anyway
Fixed a silly bug in MathStuff::rotatePoint
Added bar that shows up during object edit, allowing entry of raw offset/scale/rotation values
Update stuff.txt
- Implemented object edit rotation via dragging, hold ctrl to enable (can drag the corners)
- Changed object edit bar to scale using the center as the origin rather than bottom left
- Changed shape draw options panel to bar that automatically shows during shape draw, similar to the object edit bar
- Removed action to toggle shape draw options panel
Fixed ignored vertices being rotated and sometimes used to calculate object edit bbox
Added simple 'help text' feature, shows at top right during object edit and line/shape drawing (currently, will add more)
Add language definition for ZDaemon PATCHINF (submitted by Krawa)
Added flag to KeyBind to ignore if shift is pressed
3d mode camera moves faster when shift is held
Fixed camera turning being reversed