Added support for overriding file browse dialogs by implementing the cef DialogHandler
Change Headers to use NameValueCollection, allows for multiple values for same key, fixes Issue #336
Add OnPluginCrashed to Request handler
Fix indentation (spaces not tabs)
Remove sync over async GetSource() WinForms example
Remove the GetSource() sync-over-async wrapper from WebView again
Revert "Add GetText() sync method"

This reverts commit 9369967c7ffca456e3ac286df3ad8efafe263f95.
Merge remote-tracking branch 'remotes/upstream/master' into feature/DialogHandler
Revert change to solution
Rename params to match convention
Fix formatting, indentation (spaces not tabs) and column wrapping.
Fix indentation
Remove code duplication
Add missing deceleration keyword
Implement vector to List<string> method (just returned an empty List before)
Return result from IDialogHandler.OnOpenFile
Rename method OnOpenFile to OnFileDialog - match Cef naming (reduce confusion when consulting upstream documentation)
Add TempFileDialogHandler for easy testing of DialogHandler - generates a random filename
Spaces not tabs
Extracted the KeyType enumeration into a file of its own.