Feature/fix qmake spaces (#579)
Feature/fix qmake spaces (#579)

* fixed old command_line for win in ConfigureEnvironment

* using only modern version of command_line_env

* adding extra test for env_vars

* fixed broken test in linux for ConfigureEnvironment

* fix paths with spaces in qmake

tivek/conan,birsoyo/conan,dragly/conan,Xaltotun/conan,conan-io/conan,dragly/conan,lasote/conan,conan-io/conan,luckielordie/conan,conan-io/conan,tivek/conan,luckielordie/conan,birsoyo/conan,memsharded/conan,Xaltotun/conan,lasote/conan,mropert/conan,memsharded/conan,mropert/conan,memsharded/conan,memsharded/conan