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.
Disable check of S3 output URI for MRJOB
Merge branch 'v0.4.2-with-api-params'