Source conda 4.4.4 shell files

Conda 4.4.4 (https://github.com/conda/conda/releases/tag/4.4.0)
made some changes on how to set up conda in the shell.
This commit addresses these.

This fixes some of the discussion in #178.

bin/pyenv-sh-activate

@@ -237,7 +237,10 @@ if [ -x "${prefix}/bin/conda" ]; then
   shopt -s nullglob
   case "${shell}" in
   fish )
-    : # conda doesn't support fish
+    # conda 4.4 and above
+    for script in "${prefix}/etc/fish/conf.d"/*.fish; do
+      echo "source \"${script}\";"
+    done
     ;;
   * )
     CONDA_PREFIX="$prefix"
@@ -245,6 +248,10 @@ if [ -x "${prefix}/bin/conda" ]; then
     for script in "${prefix}/etc/conda/activate.d"/*.sh; do
       echo ". \"${script}\";"
     done
+    # conda 4.4 and above
+    for script in "${prefix}/etc/profile.d"/*.sh; do
+      echo ". \"${script}\";"
+    done
     ;;
   esac
   shopt -u nullglob