Get more packages off failing

* Exclude Memcache, close https://github.com/tanmaykm/Memcache.jl/issues/1
* Add FactCheck for FunctionalUtils, close https://github.com/zachallaun/FunctionalUtils.jl/issues/4
* Add Winston for BSplines, close https://github.com/gusl/BSplines.jl/issues/2
* Exclude AudioIO, close https://github.com/ssfrr/AudioIO.jl/issues/14
* Change Gaston to excluded, no Gnuplot on che
* Exclude LibGit2, close https://github.com/jakebolewski/LibGit2.jl/issues/8
* Exclude LibTrading, close https://github.com/StefanKarpinski/LibTrading.jl/issues/1
* Exclude SDL, close https://github.com/rennis250/SDL.jl/issues/9
* Try GLFW again, https://github.com/jayschwa/GLFW.jl/issues/7
* Allow Gtk to run with the XVFB, https://github.com/JuliaLang/Gtk.jl/issues/80