download_libs.sh doesn't properly download alternate versions

I believe I've found a bug in the download_libs.sh where if a VER is supplied (such as 0.10.1 or 0.11.0), the download fails. It looks like the script's logic doesn't match the URL structure of the CI filestore it downloads from (http://ci.openframeworks.cc/libs/).

An example URL is generated here:

openFrameworks/scripts/dev/download_libs.sh

Line 190 in 28d3b49

PKGS="openFrameworksLibs_${VER}_${PLATFORM}${ARCH}.tar.bz2"

Which is then used here:

openFrameworks/scripts/dev/download_libs.sh

Lines 31 to 34 in 28d3b49

    
           download(){ 
        
               echo "Downloading $1" 
        
               wget ci.openframeworks.cc/libs/$1 $SILENT_ARGS 
        
           }

The logic works for a default VER of master, but doesn't work for named semantic versions (ex 0.10.1) as their URLs look like http://ci.openframeworks.cc/libs/0.10.1/openFrameworksLibs_master_linux64gcc6.tar.bz2.

A solution might catch a semver VER and direct to the correct file or add an additional variable for named branches.

I found then when attempting to implement a continuous integration build system where openFrameworks is tagged to a specific version.

Thanks!

	download(){
	echo "Downloading $1"
	wget ci.openframeworks.cc/libs/$1 $SILENT_ARGS
	}