Add --emr-api-param and --no-emr-api-param options.
Added tests for --emr-api-params and --no-emr-api-params.
Added docs for --emr-api-params and --no-emr-api-params.
Fixed docs for --emr-api-params and --no-emr-api-params.
Fix typos.
Remove internal no_emr_api_params parameter. --no-api-param switch is still available.
emr_api_params overrides all other parameters.
Dedup run_and_get_job_flow() in several EMR tests
Merge remote-tracking branch 'yelp/master' into api-params

Conflicts:
	mrjob/options.py
	tests/mockboto.py
	tests/test_emr.py
Fix emr_api_params alphabetization
Merge pull request #879 from irskep/api-params

Added support for the 'api_params' parameter of boto (fixed conflicts)