Update CHANGES

* Add check for regex denial of service (Ben Toews)
GFM report format
bump version
Handle more cases of non-literals in routes

Fixes #461
markdown formatting tweaks, github file links, and test
support subpath in repo
github url support in HTML output
Merge pull request #462 from presidentbeef/fix_more_routes_without_literals

Handle more cases of non-literals in routes
GFM report format
markdown formatting tweaks, github file links, and test
support subpath in repo
github url support in HTML output
use to_markdown in format call
update non ruby1.9 line count
Merge remote-tracking branch 'upstream/master' into gfm-output-upstream
add markdown to valid format list
escape file names
move repo validation and parsing to Brakeman#set_options
Merge branch 'master' into gfm-output
Merge branch 'gfm-output' of https://github.com/github/brakeman into gfm-output

Conflicts:
	lib/brakeman/report.rb
	lib/brakeman/report/report_html.rb
	lib/brakeman/util.rb
	lib/brakeman/version.rb
	test/tests/markdown_output.rb