adds assimp formula for clang/libc++

Signed-off-by: tgfrerer <tim@poniesandlight.co.uk>
vs2010 => vs

"Unversioning" Visual Studio
Fix Visual Studio version

Now we can make it for all!
fix text color - CON_YELLOW
add an option to allow git usage
make the help more standart
first implementation of git usage
add script function - optionnal
update template for new structure
add git values in each library
catching git cloning errors and call download
add git usage in arguments
rename script function to prebuild
Merge pull request #1 from openFrameworks-cpp11/vs

Visual Studio naming
Clean up git addition

* Verbosify git usage
* Move option in private part
* Fix getopts
Clean with git
implement git-tag switching

add ability to select another version of the library on clean & download
commands
move gitclone function

... to be in a better place.
add template to all libs

avoid unset variable errors
fix wrong path for git checkout