OpenGL 3.2 support

Recent changes:

• Support of OpenGL 3.2 (MSAA on scattering and SSAO; support of signed textures for normal maps).
• Added new mesh_tessellation_paint_base base material.
• Granted access to ObjectMeshSkinned via C++ API.
• Updated C++ API documentation.
• Fixed bug with parsing '#' symbol inside define-disabled blocks in scripts.
• Memory allocator is more verbose now.
• Decreased CPU cache miss count.
• Replacing the 'inline' statement by '__forceinline' provided a huge performance speedup under Windows.
• Refactoring of XML parser.
• Less system memory consumption on DirectX 9.
• Empty maps can be declared as (:) in UnigineScript.
• Refactored KeyLine system, please refer to the documentation for more info.
• Fixed crash of import plugins on surfaces with zero vertex count.
• Fixed batch changing of light options in UnigineEditor.
• Improved seams removing algorithm for ResourceEditor.
• ObjectGrass intersects with the parent object with the use of intersection mask.
• Updated documentation on lighting ("Principles of Operation / Lighting and Shadows" section of the manual).

Here is a preliminary screenshot from the upcoming DirectX 11 benchmark based on Unigine:

The demonstration of the benchmark will be held on the major forthcoming event, stay tuned for more news.