Add check for detailed exceptions

closes #391
Also scan items in the engines path for controllers, models, etc
Add test to ensure brakeman scans engines
Updated rails4 projects with GA gem versions for Rails
rails 4 no warning for friendly model in redirect_to (friendly_id gem compatibility)
Report file for detailed exception warning

especially since JSON report requires file name
Merge pull request #396 from presidentbeef/info_disclosure_in_errors

Add check for detailed exceptions
Merge pull request #400 from aj0strow/rails4-friendlyid

rails 4 no warning for friendly model in redirect_to (friendly_id gem compatibility)
Merge pull request #397 from socialcast/engines-support

Add Support For Rails Engines
Update CHANGES
If Rails version is in Gemfile, use it

and process Gemfile before config, because config location
depends on Rails version.

Fixes #398
Only add routes that are actual names

not redirects or other calls.

Fixes #395
Merge pull request #402 from presidentbeef/use_gem_version_of_rails

If Rails version is in Gemfile, use it
Merge pull request #403 from presidentbeef/redirect_in_route

Only add routes that are actual names
Update CHANGES
README tweaks
Add tests for command injection of literals
Don't warn on literals interpolated in system calls

and other safe-ish values
Merge pull request #404 from presidentbeef/reduce_command_injection_fps

Reduce command injection false positives
Change highline dependency to 1.6.20