python: allow config params in scr.init

[adammoody]

Just hacking around since python is cool. Not sure we want to support this, so I'll leave it hanging as WIP.

This extends scr.init() to accept SCR configuration parameters. One may specify a single parameter as a string, or a set of params using a list or dict. Those are internally passed to scr.config() before calling SCR_Init. For example, all of the following would be valid:

# as str
scr.init("SCR_DEBUG=")
scr.init("SCR_DEBUG=1")

# as list
scr.init(["SCR_DEBUG=1", "SCR_COPY_TYPE=SINGLE"])

params = list()
params.append("SCR_DEBUG=1")
params.append("SCR_CACHE_SIZE=2")
scr.init(params)

# as dict
scr.init({"SCR_DEBUG": 1, "SCR_COPY_TYPE": "SINGLE"})
scr.init({"SCR_DEBUG": None, "SCR_COPY_TYPE": "SINGLE"})

params = dict()
params["SCR_DEBUG"] = 1
params["SCR_CACHE_SIZE"] = 2
scr.init(params)

That feels more python-like, but I'm not sure it buys much over just calling scr.config several times, e.g.,:

scr.config("SCR_DEBUG=1")
scr.config("SCR_CACHE_SIZE=2")
scr.init()

Unless users really need something like this, it's probably not worth the extra effort to develop, test, maintain, and document. If it is requested, we could add similar logic to scr.config to take a set of params in one call.