Org Metadata Indexing Improvments

Updates to org metadata loading.
* Reuse SFDC client
* Unselect all and sort on save
* Select on load depending on active/selected or package.xml (some
issues?)
*

Conflicts:
	mm/lib/mm_util.py
Metadata index performance and functionality enhancements

Deselect all metadata when loaded, then select based on "selected" key
or package.xml when metadata is requested
Response time fix

Correct calculation of the response time taken based on config.mm_start
and the current time of the success response
Merge pull request #51 from doublesharp/patch_index_metadata

Patch index metadata