Visual fixes & Create DebugBar class & benchmark class removed (issue #8, #9, #5)

This version introduces multiple enhancements:

removed benchmark class, functionality was replaced by DebugBar
added some new functionalities (Zend\Debug::dump, exceptions, memory usage in timeline)
allow to give object as collector in DebugBar
some style changes

Details of additions/deletions below:
--------------------------------------------------------------

Added:      Debug/Collectors/TimeCollector.php
            -- Added --
                extends time data collector functionality

Modified:   Debug/Debugger.php
            -- Added --
                allow to lunch some basic collector classes

Modified:   examples/debugbar.php
            -- Added --
                some examples

Modified:   composer.json
            -- Added --
                zendframework/zend-escaper in 2.* version

Modified:   Debug/Assets/dark.css
            -- Updated --
                some style changes and new styles for debugbar dark version

Modified:   Debug/DebugBar.php
            -- Added --
                usage of some new classes
                EXCEPTION
                dump handle Zend\Debug::dump() function
                addException Adds an exception to be profiled in the debug bar
            -- Updated --
                __construct changed basic debugbar class from DebugBar\StandardDebugBar to ClassBenchmark\Debug\Debugger
                setCollector name variable can be an instance of lunched data collector object

Removed:    Performance/Benchmark.php
            -- Removed --
                unused class