Included actual HabitRPG readme info

Was previously just the Ionic framework readme, to include saying issues were disabled on this repo and to report all bugs to the Ionic Forum.

Without actually getting a local copy up and running, I don't know how important the Ionic readme information is, so I just added HabitRPG info and augmented the issue reporting section.
we use a custom build not ionic's one so instead of `ionic serve` just run `gulp`