Code: Refactor and minor improvements.
Merge pull request #394 from am11/master

Code: Refactor and minor improvements
File icons: Update the .bundle icon
Markdown: Enabled custom CSS button. Fixed #396
Root folder cleanup
Tests: Fix spelling errors
Tests: Fix FluentAssertion extension messages

Make messages consistent with
FluentAssertions built-in messages
Tests: Clean up VSTest class

Rename to VSHost
Use property instead of method
Tests: Reorganize test folders

Fix casing, remove unnecessary folders
Merge pull request #397 from SLaks/test-cleanup

Cleanup unit tests
Solution: Fixed spelling of LICENSE
Commands: Change PkgCmdIDList to enum
Commands: Rename command IDs to follow C# conventions

Remove cmd Hungarian notation
Use UpperCamelCase
Remove suffixes

This giant commit consists of nothing but rename refactorings.
I also removed a few unused enum members.
Commands: Merge GUIDs & IDs files

Also rename class & enum
Code: Refactored WriteFile method.
Test: Change settings default host.
Merge pull request #398 from am11/master

Misc fixes
Commands: Refactor encoding command
Commands: Take CommandId as a parameter

Slight simpliciation

Also change ZenCoding to not use magic numbers
Analysis: Remove unused parameter

Also remove unnecessary await, & fix MIME mistake