Remove support for {min,max} property path length spec from SPARQL parser

support for specifying property path length with a lower and upper bound (e.g. {1,5} ) was removed from the SPARQL 1.1 Query Language specification in the July 24 Working Draft. Currently, the Sesame SPARQL parser still accepts the construction, however, its semantics are undefined and continued support for the functionality is likely to be unoptimized and buggy. Instead, we should conform to the official spec and remove the functionality.