message: fixing bug in mlpack readme
diff: @@ -6,16 +6,18 @@ To build the mlpack optimizer plugins, you must pull down ensmallen and armadill
  $ mkdir $HOME/.xacc_tpls
  $ cd $HOME/.xacc_tpls
  $ git clone https://github.com/mlpack/ensmallen
  -$ git clone https://gitlab.com/conradsnicta/armadillo-code
  +$ git clone https://gitlab.com/conradsnicta/armadillo-code armadillo
  ```
  Now configure XACC, pointing to the appropriate ensmallen and armadillo-code installs
  ```bash
  +$ cd $HOME
  $ git clone --recursive https://github.com/eclipse/xacc
  $ cd xacc && mkdir build && cd build
  $ cmake .. -DXACC_ENSMALLEN_INCLUDE_DIR=$HOME/.xacc_tpls/ensmallen/include
  -DXACC_ARMADILLO_INCLUDE_DIR=$HOME/.xacc_tpls/armadillo/include
  + [add any other cmake args you may need, see top-level readme]
  $ make -j4 install
  ```
  That should install the mlpack optimizer!
  \ No newline at end of file
  