Savanna (#4856)

Installing the stable version 0.5 through the checksummed tar.gz does not fetch the git submodule in the package.
The submodule appears as an empty directory.

Thus, clone the commit tagged as v0.5 using git to get around this issue

* savanna: modified adios dependency spec
* Replaced adios+staging with adios+flexpath+dataspaces
* savanna: Enabling fortran support in adios by default
* savanna: reverting to variant 'staging' for enabling all staging transports

var/spack/repos/builtin/packages/savanna/package.py

@@ -36,13 +36,14 @@ class Savanna(MakefilePackage):
 
     version('develop', git='https://github.com/CODARcode/savanna.git',
             branch='master', submodules=True)
-    version('0.5', '3f13adf29ec30f4acb2ba3fa07ed12b2')
+    version('0.5', git='https://github.com/CODARcode/savanna.git',
+            tag='0.5', submodules=True)
 
     variant('tau', default=False, description='Enable TAU profiling support')
 
     depends_on('mpi')
     depends_on('stc')
-    depends_on('adios +staging')
+    depends_on('adios +fortran +staging')
     depends_on('mpix-launch-swift')
     depends_on('tau', when='+tau')