Updated documentation for VS and shields

Updated What's new, added a Shield compat matrix, added some info about
Visual Studio Specificities.
Updated Documentation after rendering review

spelling, broken links, table format
doc updates - format fixes
table fixes
table spacing fixes
Added release note about USB host
Code reviews changes

1) Used Markdown version of button
2) Added that precompiled headers are disabled by default
fixed spacing
updated newlines
Merge pull request #97 from IoTDan/develop

Updated documentation - Visual Studio specificities, Shield compat table, what's new update