Adjust for conda-build 2.1.4.

* update prefix path to the conda-build test environment.
* Use `--dirty` instead of deprecated `--keep-old-work`.

Author: pavoljuhas

.travis.yml

@@ -75,8 +75,8 @@ before_install:
   - $NOAPT || popd
 
 install:
-  - $NOMC || conda build --keep-old-work conda-recipe
-  - $NOMC || MYCONDATESTENV="$(ls -td ~/mc/conda-bld/conda-recipe_*/_t_env | head -1)"
+  - $NOMC || conda build --dirty conda-recipe
+  - $NOMC || MYCONDATESTENV="$(ls -td ~/mc/conda-bld/${MYNAME}_*/_t_env | head -1)"
   - $NOMC || source activate ${MYCONDATESTENV:?"conda test environment not found"}
   - $NOMC || conda list  --export ${MYNAME} > /tmp/mypackage.txt
   - $NOMC || source activate root