Fix Visual Studio build in cmake
Build common as OBJECT library in cmake

Set common as OBJECT library to create correct chewing.lib. See [1] for detail
information.

[1] http://stackoverflow.com/a/11448878/79816
Manual set output path for Visual Studio

Visual Studio appends configuration (Debug, MinSizeRel, Release,
RelWithDebInfo) into output path, whith is not desirable because we need to
know output path for custom command.