added navigation buttons
added $location config
updated ejgQuoteCtrl to provide quote history
improved formatting and comments
RandomQuoteCtrl reimplemented to QuoteCtrl; now provides history usage and get quote by id
implemented QuoteHistoryService to track seen quotes and navigation between them; also with browser location setting (sets quote id as hash)
fixed en-/deable of previous button
beautified
simplified adding of new objects

after: only object (containing id!)
before: object and id
quote will be returned directly

removed enclosing object (see previous commit)
renamed argument when promise gets rejected
only html formatted quotes are added to the history now (fixed some errors)
histPntr now initialy -1
fixed hasPrevious function
set object id hash
fixed returning of next quote when histPntr is not at head of history
removed debug command
renew hash of location when returning previously seen quote
Merge branch 'quote-history'