Upgrade version in Installation documentation

Upgrade to latest ravenjs version 1.1.13 in Installation documentation
Merge pull request #201 from pkuczynski/patch-1

Upgrade version in Installation documentation
Mark ugly frame as `in_app`
Only ignore messages that don't have a type or message

Underscore.js throws a plain TypeError with no arguments. ugh.
Be more specific and just filter "Error" types since I have no idea what is going on
1.1.14