Modify base::convert_to() undefined implementation

GCC shows divide-by-zero warnings, so it is better in this way.
Fix ui::Manager::pumpQueue() error when compiling in debug mode
Change PACKAGE name to Aseprite
Fix warning: Remove AL_CONST modifier from free_config_entries() function
Add support for Unicode file names on Windows

- Fixed issue #46: open .png files with Unicode chars
- Fixed issue #150: ability to uncompress program in folders w/Unicode chars
- Added base::utf8_iterator
- Added base::FileHandle
- Added base::get_app_path()
- Modified ui::KeyMessage::ascii() -> unicodeChar()
- Removed JI_NOTEXT flag
- Added app::XmlDocumentRef class and app::open_xml() function
- Added support for Unicode text exchange with Win32 clipboard
Merge branch 'dev' of git@github.com:dacap/aseprite.git into dev
Merge branch 'dev' of git@github.com:dacap/aseprite.git into dev
Replace JRect/jrect struct with gfx::Rect

- Replaced Widget::rc -> Widget::m_bounds private member.
- Added Widget::offsetWidgets() method.
- Removed View::displaceWidgets().
Encapsulate Image implementation (private members, accessors, iterators, etc.)

- Rename _rgba/_graya to raster::rgba()/graya()
- Add raster::color_t type (alias for uint32_t)
- Rename raster::GfxObj to Object. And GfxObj::getType() to Object::type()
- Move conversion from raster::Image/Palette to Allegro BITMAP/RGB
  to raster/conversion_alleg.h file
- Add raster/color_scales.h
- Rename image_* functions to raster/primitives.h
- Reimplement ink processing with templates instead of macros
Merge branch 'dev' of git@github.com:dacap/aseprite.git into dev
Fix warnings using Win32 Unicode functions instead of ANSI functions in curl lib
Avoid calling Image::getPixelAddress() (virtual function) in several ImageImpl functions
Specialize ImageImpl::clear for Indexed and Bitmap images
Add ImageBuffer class

It tries to mitigate issue #239, but it's not a full fix yet. A good
possibility would be to change the internal structure of images, creating
tiles. So we don't need to allocate/copy/clear/etc. huge images in each
step.
Improve put/get_pixel_fast() functions to avoid virtual function call
Update TODO.md
Improve creation of Dirty() instance (fix issue #239)

Now Dirty() ctor receives the bounds, so we don't need to iterate over
the whole image to find/shrink the modified region.
Fix bug where dirty bounds are out of the image bounds
Show an error if we cannot create a ToolLoopImpl

The main issue at the moment is that a std::bad_alloc exception can be
thrown if there isn't enough memory available when the user click the
sprite editor to start drawing.
Minor change: Make Splitter::getPosition() inlined