Add ignore_routes option

[mintuhouse]

I use to skip routes which generate an annotation which includes local path e.g.,

#     /mobile       #<Rack::Builder:0x0000000a2ff800 @run=Mobile::Dispatch, @map=nil, @use=[#<Proc:0x0000000a30e2d8@/home/hasan/.rvm/gems/ruby-2.1.7@gogo/gems/rack-1.5.5/lib/rack/builder.rb:86>]>
#     /resque       #<Resque::Server app_file="/home/hasan/.rvm/gems/ruby-2.1.7@gogo/gems/resque-1.25.2/lib/resque/server.rb">

which causes a file change after every annotate run - leading to bad churn on codeclimate

add ignore_routes: "#<" to config options to skip such routes

[ctran]

Please re-submit against the "develop" branch.

[mintuhouse]

#315
resubmitted against develop