add style for Download NuGet button
add style for Download NuGet button

JetBrains/teamcity-nuget-support,stormleoxia/teamcity-nuget-support,JetBrains/teamcity-nuget-support,stormleoxia/teamcity-nuget-support,stormleoxia/teamcity-nuget-support,JetBrains/teamcity-nuget-support,JetBrains/teamcity-nuget-support