Add Wincache

Updated comments

Check for Wincache existence in constructor

Normalized markup

Add Wincache test

Tie Wincache test to test index
remove two DOS EOL
Code clean
add Minify::getCache() and Minify_Cache_Abstract that all cache classes must implement
add Null cache
if no Cache is defined, create Minify_Cache_Null
rename Minify_Cache_Abstract class to Minify_Cache_Interface interface
Rename cache interface in pref for namespaces
remove unneeded pack()