Merge with default

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branch : develop
Fix VS2010 compiler error

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branch : develop
Fix VS2010 compiler error, VS2010 has not implemented std::round()

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branch : develop
MainWindow2: fix unstable problem os newDocument(). rename object => m_object

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branch : develop
PencilDef: define constant string PENCIL_WINDOW_TITLE

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branch : develop
MainWindow2: rename saveForce() => saveDocument().

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branch : develop