Rationalize and update Visual Studio projects and packaging.
Merge branch 'evoskuil/master'
Update packaging metadata.
Merge pull request #960 from evoskuil/master

Rationalize and update Visual Studio projects and packaging.
Update packaging metadata.
Merge pull request #961 from evoskuil/master

Update NuGet packaging metadata.
Incorporate libsodium option and linkage, generalize, update packaging.
Merge branch 'evoskuil/master'
Merge pull request #964 from evoskuil/master

Incorporate libsodium option and linkage, generalize, update packaging.
Update VS build configurations.
Merge pull request #965 from evoskuil/master

Update VS build configurations.
Merge pull request #968 from hintjens/master

Fixed issue #967
Merge pull request #970 from mditzel/master

Fix issue #969
Fix issue #969
Fix issue #971
Merge pull request #972 from mditzel/master

Fix issue #971
Change ToolsVersion to 4.0 for VS2010
Reference default locations for libsodium for VS2010
Merge pull request #973 from HughPowell/master

Change ToolsVersion to 4.0 for VS2010
Fixed mingw poll detection