Merge tag '3.1.0' into develop

Add nuget targets for .NET 4.5 and portable

UnitsNet.nuspec

@@ -2,7 +2,7 @@
 <package xmlns="http://schemas.microsoft.com/packaging/2011/08/nuspec.xsd">
   <metadata>
     <id>UnitsNet</id>
-    <version>3.0.0</version>
+    <version>3.1.0</version>
     <title>Units.NET</title>
     <authors>Andreas Gullberg Larsen</authors>
     <owners>Initial Force AS</owners>
@@ -12,30 +12,9 @@
     <description>Units.NET gives you all the common units of measurement and the conversions between them. It is light-weight, unit tested and supports PCL.</description>
     <summary>Simplifies working with units of measurement.</summary>
     <iconUrl>https://raw.githubusercontent.com/InitialForce/UnitsNet/develop/logo-32x32.png</iconUrl>
-    <releaseNotes>v3.0.0: Clean up naming of units. Add information unit.
-
-New:
-* Add information units for bit, byte, kilobit, kilobyte, kibibit, kibibyte and so on up to exabyte
-
-Breaking changes:
-* Delete OtherUnit.Piece
-* Move OtherUnit.Table/Teaspoon to Volume
-* Rename Month30Days Year365Days units to Month and Year
-* Fix plural naming of Pressure.KilogramsForcePerSquareCentimeterInOnePascal
-* Fix plural naming of Ratio.PartsPer-units
-* Custom units added manually via UnitSystem.MapUnitToAbbreviation()
-
-Fixes:
-* Fall back to US English culture when parsing/getting abbreviations
-* Fall back to custom string if no abbreviation defined for unit
-
-Behind the scenes:
-* Replace T4 templates with PowerShell + JSON templates
-* Support custom tolerance per unit in tests
-* Support decimal and long base unit types (decimal used in Information unit)
-* Move code more consistently into Custom/GeneratedCode folders
-* Fix misc R# warnings
-* Match R# cleanup profile in generated code
+    <releaseNotes>v3.1.0: Add more nuget targets for .NET 4.5
+* .NET 4.5.1
+* Portable profile 259 (portable-net45+wp80+win8+wpa81)
 </releaseNotes>
     <copyright>Copyright © 2007-2014 Initial Force AS</copyright>
     <language>en-US</language>