fix text file busy error while building docker (conda)

Author: oesteban

Dockerfile

@@ -175,7 +175,7 @@ RUN conda config --add channels conda-forge --add channels intel && \
     chmod +x /usr/local/miniconda/bin/* && \
     conda config --set always_yes yes --set changeps1 no && \
     conda update -q conda && \
-    chmod +x /usr/local/miniconda/bin/* && \
+    chmod +x /usr/local/miniconda/bin/*; sync && \
     conda install -y mkl=2017.0.1 \
                      numpy=1.11.2 \
                      scipy=0.18.1 \