app : Generic - REST Api wrappers + UI Classes

Added Generalised Api and UI classes like :
1. HttpPageGetter           --> GlusterHttpGetApi
2. HttpPostRequests         --> GlusterHttpPostApi
3. HttDeleteRequests        --> GlusterHttpDeleteApi
4. AsyncTaskParameters      --> AsyncTaskParameter
5. AsyncTaskPostParameters
to not take ints to decide what kind of object is expected.
Now it does all conversions generically.

Signed-off-by: Anmol Babu <anbabu@redhat.com>
Merge branch 'clean_code' of github.com:anmolbabu/glustermobile into clean_code

Signed-off-by: Anmol Babu <anbabu@redhat.com>