Merge pull request #16 from bblankrot/patch-pyplot-err

changing pygui backend to tk before `using PyPlot`

.travis.yml

@@ -13,7 +13,7 @@ notifications:
 env:
  - PYTHON=Conda-python
 script:
-  - export LD_LIBRARY_PATH=$HOME/.julia/v0.6/Conda/deps/usr/lib; LD_PRELOAD=${HOME}/.julia/v0.6/Conda/deps/usr/lib/libz.so julia -e 'Pkg.clone(pwd());Pkg.test("ParticleScattering"; coverage=true);'
+  - export LD_LIBRARY_PATH=$HOME/.julia/v0.6/Conda/deps/usr/lib; LD_PRELOAD=${HOME}/.julia/v0.6/Conda/deps/usr/lib/libz.so julia -e 'using PyCall;pygui(:tk);using PyPlot;Pkg.clone(pwd());Pkg.test("ParticleScattering"; coverage=true);'
 before_install:
   - julia -e 'ENV["PYTHON"]=""; Pkg.add("Conda"); using Conda; Conda.update(); Conda.add("matplotlib"); Conda.add("basemap"); Pkg.add("PyCall"); Pkg.build("PyCall"); Pkg.add("PyPlot");'
 after_success: