fix compiler switch in example 5
replace deprecated header_search_paths with installable_headers
fix compiler warning, remove semicolon
add spec for local_config with namespace
Revert "add spec for local_config with namespace"

This reverts commit 84d6255ffae61c142377ca41b7162c390d6baa37.
add spec for local_config with namespace
local_config fix in combination with namespace
Merge pull request #23 from bhase/local_config

local_config in combination with namespace