Reduce memory allocation per request and other optimizations

Reduce object allocation and memory allocation per request:

• Better use of the methods of StringBuilder in StringOutput (done)
• Dummy in StringHelper containsNonWhitespace to prevent regex check (done)
• The velocity templates are cached in a LRU Map with a size of 89, move it the infinispan (done)
• The user activity logger write 2 - 4 info messages, generate stack traces and exceptions if it don't found a resource (done)
• In component, only secure the dispatch ID for javascript use if it's not a generated number (done)
• Optimize enrollment table (which make several database queries per row) (done)
• Feed must take the author/modifier names from the user manager cache (done)
• Implement a prewarm infrastructure to fill some critical caches of OpenOLAt at start like: velocity templates, display names of users, Onyx resources (done)
• Don't create the PreferencesImpl in UserImpl constructor (done)