Updated ShowKeyboardInput and ShowMessageBox methods
Updated ShowMarketplace method
[WinStore] Add check at LoadFromStream method of Texture2D

WIC doesn't not support non-seekable streams.

For example when you load images from the web an exception is throw by
DX but it's not very helpful to identify the problem.

http://sharpdx.org/forum/5-api-usage/379-sharpdx-wic-bitmapdecoder-class-not-working-with-outside-url
Merge pull request #3120 from nkast/tncAddExceptionToPlatformFromStream

[WinStore] Add check at LoadFromStream method of Texture2D
Fixed null reference exception in Guide when called from threadpool threads
Added support for BGRA444 and BGR565 in PixelBitmapContent
Pixed pipeline crash with small letters in font textures
Fixed missing character width in FontTextureProcessor
Fixed missing line spacing in FontTextureProcessor
Fixed incorrect cropping in FontTextureProcessor
Only compress font textures if asked to
Only generate square, power of two textures if compression is enabled
Added premultiply alpha to FontTextureProcessor
Fixed cropping on the X axis in FontTextureProcessor
ResolveRelativePath fixes for iOS
Merge pull request #3132 from SongArc/feature/content_texturefix

Added support for BGRA444 and BGR565 in PixelBitmapContent
Merge pull request #3124 from SongArc/feature/win8_dispatcherfix

Fixed null reference exception in Guide on Windows 8
Added PremultiplyAlpha as parameter to compression
Merge pull request #3133 from SongArc/feature/content_texturefontfix

Content pipeline texture fonts fixed
Fixed default values in FontTextureProcessor