continue work on advbrowser (PHP)

[jgonggrijp]

@zed0 left the beginning of a fun game on his advbrowser branch: a textadventure that lets you browse webpages as if they were rooms. He informed me that he might want to work on it again in the future, but anyone is welcome to work on it in the meanwhile.

In order to get your own local branch for working on this, I suggest that you run the following commands (of course you don't need to add zed0 again if you already had him):

git remote add -f zed0 git://github.com/zed0/the-red-spider-project.git
git checkout zed0/advbrowser
git checkout -b advbrowser
git pull upstream master

After this you can just follow the regular workflow as described on the wiki.

Note: for historical reasons the branch also contains the source code of advshell, another adventure game. Please don't touch that file while on the advbrowser branch; if you want to work on advshell as well, do it on a separate branch: see issue #37.