moved building instructions into different md files

BUILDING_ON_MAC.md

@@ -0,0 +1,22 @@
+# Building on Mac OSX
+1. install Xcode and Xcode Command Line Utilites
+2. start Xcode, settings -> Locations, activate your Command Line Tools
+3. install Qt Creator
+4. install brew https://brew.sh/
+5. `brew install boost openssl rapidjson`
+6. build the project using Qt Creator
+
+If the Project does not build at this point, you might need to add additional Paths/Libs, because brew does not install openssl and boost in the common path. You can get their path using
+
+`brew info openssl`
+`brew info boost`
+
+The lines which you need to add to your project file should look similar to this
+
+```
+INCLUDEPATH += /usr/local/opt/openssl/include
+LIBS += -L/usr/local/opt/openssl/lib
+
+INCLUDEPATH += "/usr/local/Cellar/boost/1.67.0_1/include"
+LIBS += -L"/usr/local/Cellar/boost/1.67.0_1/lib"
+```