Added validation for networks parameter value

A validation check is added for networks parameter value.
In server create request body, if networks parameter value
is not stored in a list then 'Bad networks format' error
is thrown with bad request exception.A new test case is
added to verify whether it is returning bad request exception
when invalid syntax is used.

Fixes: bug #1175683

Change-Id: I457a1626c56281f89d8c4a606ccc0d0e3aea05fa
Remove locals() from scheduler filters

Just removed locals() and replaced it with an explicit dicionary.

Change-Id: Id476a684abde36238b5abfe8ce4c3ddb0874423b
Merge "Remove locals() from scheduler filters"
Merge "Added validation for networks parameter value"