Separate HTML template from code

vCheck.ps1 - Separated all HTML code from the vCheck.ps1 script to allow creation of
Style templates, migrated existing HTML code into a Default style.

Plugin 00 - Check for existing connections to the vCenter server and re-use if they
exist. Saves duplicate connections and results.

Created /Style/ Folder to contain styles.
Created /Style/Default folder to contain default style
Created /Style/Default/Style.ps1 to contain CSS and HTML code
Copied header.jpg to /Style/Default/header.jpg
Added $Style = "Default" to GlobalVariables.ps1