Adding DotNet restore support

src/app/FakeLib/DotNetCLIHelper.fs

@@ -0,0 +1,59 @@
+/// Contains a task which can be used to run [DotCover](http://www.jetbrains.com/dotcover/) on .NET assemblies.
+module Fake.DotNet
+
+open Fake
+open System
+open System.Text
+
+/// DotNet Restore parameters
+type RestoreParams = {
+    /// ToolPath - usually just "dotnet"
+    ToolPath: string
+
+    /// Working directory (optional).
+    WorkingDir: string
+
+    /// A timeout for the command.
+    TimeOut: TimeSpan
+
+    /// Whether to use the NuGet cache.
+    NoCache : bool
+}
+
+let private DefaultRestoreParams : RestoreParams = {
+    ToolPath = "dotnet"
+    WorkingDir = Environment.CurrentDirectory
+    NoCache = false
+    TimeOut = TimeSpan.FromMinutes 30.
+}
+
+/// Runs the dotnet "restore" command.
+/// ## Parameters
+///
+///  - `setRestoreParams` - Function used to overwrite the restore default parameters.
+///
+/// ## Sample
+///
+///     DotNet.Restore 
+///         (fun p -> 
+///              { p with 
+///                   NoCache = true })
+let Restore (setRestoreParams: RestoreParams -> RestoreParams) =
+    traceStartTask "DotNetRestore" ""
+
+    try
+        let parameters = setRestoreParams DefaultRestoreParams
+        let args =
+            new StringBuilder()
+            |> append "restore"
+            |> appendIfTrue parameters.NoCache "--no-cache"
+            |> toText
+
+        if 0 <> ExecProcess (fun info ->  
+            info.FileName <- parameters.ToolPath
+            info.WorkingDirectory <- parameters.WorkingDir
+            info.Arguments <- args) parameters.TimeOut
+        then
+            failwithf "Restore failed on %s" args
+    finally
+        traceEndTask "DotNetRestore" ""

src/app/FakeLib/FakeLib.fsproj

@@ -150,6 +150,7 @@
     <Compile Include="NuGet\Install.fs" />
     <Compile Include="NuGet\NugetVersion.fs" />
     <Compile Include="TestFlightHelper.fs" />
+    <Compile Include="DotNetCLIHelper.fs" />
     <Compile Include="DotCover.fs" />
     <Compile Include="PaketHelper.fs" />
     <Compile Include="PaketTemplateHelper.fs" />