Debugger bar: fixed page bottom gap caused by debug bar
Debugger: CSS styles moved to extra files
Debugger: removed unused CSS
Debugger: HTML mode is off with CLI SAPI

headers_list() is always empty with PHP_SAPI === 'cli'. PHP manual says: "Headers will only be accessible and output when a SAPI that supports them is in use".
Dumper: html mode detection is the same as Debugger's one
Dumper: terminal 'screen' is color-capable too
Dumper: terminal color dump only if STDOUT is a terminal

This avoid printing escaping sequences in cases of redirection like:
  php dump.php > output.log
  php dump.php | less
typos
Debugger: accept multiple e-mails for error notifications [Closes #803]
Debugger: separated CSS & JS for Dumper to files dumper.css & dumper.js [Closes #871]
Diagnostics: Logger implodes message to single line
Diagnostics: Logger $priority argument can be NULL
Debugger: Remove PHP 5.2 check for $e->getPrevious() and $e->previous
used ENT_IGNORE flag to ignore non UTF-8 characters in error messages and file paths
debug_backtrace() is called with parameter DEBUG_BACKTRACE_IGNORE_ARGS
tests: some tests renamed
tests: improved readability using function test()
Debugger: in MSIE sends error 503 instead of 500 to ensure error page is displayed
Debugger: refactoring of $errorTypes
Debugger: refactoring, added Helpers::fixStack