bigswitch-vns: Fix since version in apis, add spring annotation to fix NPE

Signed-off-by: Rohit Yadav <bhaisaab@apache.org>
netapp: Fix as pluggable service and return list of apis it offers

Signed-off-by: Rohit Yadav <bhaisaab@apache.org>
CLOUDSTACK-1210: Fix pluggable service, apiserver, mgmt server impl, api-discovery

- Mgmt server impl is a pluggable service, fix it's method
- Fix getCommands() to return all cmd api classes supported by this mgmt server
- For api-discovery, get commands from pluggable services only, don't use reflections
- Don't use reflections in ApiServer, iterate pluggableservices
- Fix api discovery unit test
- The fix was done automatically using following python program along with
  following step:

1. Get all apis provided by default mgmt server, all of them are in cloud-api now
   cd api/src/org/apache/cloudstack/api/command
   find . >> apis
2. For all apis, generate java code that adds the class to the cmdList arraylist:
   f = open('apis', 'r')
   data = f.read()
   f.close()
   output = ""
   for a in data.split('\n'):
     output += "cmdList.add(%s);" % a.split('/')[-1].replace('.java', '.class')
   # wrote output to a file, copied content to mgmt server impl's getCommands()
   # similarly, fixed import statements using same code, splitting on /

Testing:
Ran apiserver, put breakpoints in ApiServer's init() where classes are processed
Total cmd classes found by reflections (ReflectUtil) = 354
Total cmd classes found by getCommands for all pluggable services = 354

Next, copied the comma separated values for each set to a string in ipython, a & b
set(a).difference(set(b)) returned null.

The above test implies both set of cmd classes found by both methods, i.e. using
reflections and using getCommands() had same set of apis and all were unique.

Conclusion:
The changes are idempotent and don't break api server's cmd class api discovery
processing.

BUG-ID: CLOUDSTACK-1210

Signed-off-by: Rohit Yadav <bhaisaab@apache.org>