Travis config 

In order to have a fixed travis profile, where the right settings are respected, i introduced a config for the memory. Before that it was easy to forget to change back for example the buffer load factor which led to errors in the travis build. Therefore i introduced a dedicated travis profile + config for memory settings.

In addition i added the entry profile.user.conf to the gitignore and suggest to use this profile for local testing of each user, so there are hopefully no unexpected errors in the travis build anymore.

(As soon as pr #23 is merged i will rebase)