improve Mac install instructions

docs/pages/getting-started/installation.md

@@ -64,11 +64,18 @@ You need to install the following free libraries:
 
 We suggest using [Homebrew](http://brew.sh/) for the first 4:
 
+    $ brew install cmake
     $ brew install cgal
     $ brew install gdal
-    $ brew install cmake
+    $ brew install yamp-cpp
+
+For LASlib/LASzip, get the source code from the LAStools repository and use the `CMakeLists.txt` included in the root folder:
+
+    $ git clone [email protected]:LAStools/LAStools.git
+    $ cmake .
+    $ make install
 
-For LASlib/LASzip, follow the instruction and use the `CMakeLists.txt`.
+If you're getting the clang compilation error `character too large for enclosing character literal type`, comment out [the line](https://github.com/LAStools/LAStools/issues/103) causing the problem and try again.
 
 To compile 3dfier: