Add test_apropos_should_also_search_settings_description() to make sure that:
Add test_apropos_should_also_search_settings_description() to make sure that:

    apropos 'environment variable'

searches all settings description and returns a topic related to:

    target.process.env-vars


git-svn-id: b33bab8abb5b18c12ee100cd7761ab452d00b2b0@124841 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb