documentation: improve readability; line length, indentation, highlighting.
related pull requests: #1036 #1038 #1043
Merge pull request #1044 from crate/l/improve-docu-readability

documentation: improve readability; line length, indentation, highlighti...
added IndexReferenceInfo to hav a notion if index columns

and forbid match on dynamic references
update changes
Merge pull request #1046 from crate/m/match_fix

M/match fix
add bulkArgs to SQLRequest
Added benchmark test to compare bulk inserts with multiple insert statements
check bulk_args for mixed types
use BulkShardProcessor instead of TransportBulkAction