Normalize documentation template

Change template.html so that it includes te link header to the
related fsharp.org projects. Change GitHub ribbon to be gray like
the other sites as well.
Use style.css from FSharp.Data for consistency
Fix some typos
Various cleanup to the documentation

-Use backticks to call out identifiers.
-Don't refer to methods as "functions."
-Fix some grammatical errors and try to use a consistent style.
-Add some missing titles.
-Fix Further Samples code to not overlap sidebar and uncomment the
 large commented section so that it formats correctly.
-Fix intro paragraphs to avoid verbatim restating of the article
 sumamry.
Refer to project as "F# Charting" in documentation

This commit modifies the headers as well as the text of the
documentation to refer to the project as "F# Charting" as opposed
to "FSharp.Charting," except when referring to the NuGet package,
namespace, assembly, etc. This is the convention followed by the
F# Data documenation as well.

To avoid redundancy, I also changed the home page title to
"F# Charting: Library for Data Visualization" as opposed to
"F# Charting: The F# Charting Library." Feel free to change if you
think that doesn't work or come up with a better title.
Merge pull request #46 from lasandell/CleanupDocs

Documentation Cleanup