Updating CSharpCodeVisitor to generate implicit expressions on a single line

Fixing 151
Hmm, this actually doesn't really fit for what we're trying to do, we don't happen to care about the design time line mappings at all so the `chunk.Start` and `contentSpan.Length` are unneeded properties that we pass in.

It might be nice to have another method or overload that ignores these properties and prints out only the line pragmas for the start/end of the section (aka no line mappings).  Another possibility is to just write out the begin/end portions of the the line pragmas.

```C#
#line 1 "foo.cshtml"
...
#line default
#line hidden