Log Message:
Update ruby-bundler to 1.10.6.

## 1.10.6 (2015-07-22)

Workarounds:

  - only warn on invalid gemspecs (@indirect)

Bugfixes:

  - fix installing dependencies in the correct order (#3799, @pducks32)
  - fix sorting of mixed DependencyLists (#3762, @tony-spataro-rs)
  - fix `install_if` conditionals when using the block form (@danieltdt)