Fix method and parameter descriptions
Fix method and parameter descriptions

Method and parameter descriptions are being corrected for typo
mistakes and increase readability. In parameter 'context' description,
it should be 'for' instead of 'from'. Similar few other typos are
being addressed.

Change-Id: I6ff2072bf9dcd5ee2414c8b6d000aa155ee29be0
Closes-Bug: #1490379

mjbrewer/testindex,jay-lau/magnum,Alzon/SUR,mjbrewer/testindex,eshijia/SUR,Tennyson53/SUR,ArchiFleKs/magnum,Tennyson53/magnum,Tennyson53/SUR,openstack/magnum,dimtruck/magnum,annegentle/magnum,dimtruck/magnum,annegentle/magnum,ArchiFleKs/magnum,eshijia/magnum,Alzon/SUR,mjbrewer/testindex,Tennyson53/magnum,eshijia/SUR,openstack/magnum,eshijia/magnum