Ensured that WiX candle definitions are enclosed in quotes

[galpin]

What You Are Seeing?

WiX candle fails when a define is added that includes a space in the value because the command line runner does not enclose the value in quotations.

What is Expected?

The command line arguments should enclose define values in quotes.

What version of Cake are you using?

0.15.0

Are you running on a 32 or 64 bit system?

64-bit

What environment are you running on? Windows? Linux? Mac?

Windows

Are you running on a CI Server? If so, which one?

No

How Did You Get This To Happen? (Steps to Reproduce)

WiXCandle("app.wxs", new CandleSettings
{
    Defines = new Dictionary<string, string>
    {
        { "ProductName", "Amazing Product Name" }
    }
});

Output Log

Executing: "tools/WiX.Toolset/tools/wix/candle.exe" -arch x86 -dProductName=Amazing Product Name "app.wxs"
candle.exe : error CNDL0103 : The system cannot find the file 'Product' with type 'Source'.