No proper encoding of index terms

[engelsanchez]

An EQC test I'm writing is finding many binaries that the http client does not support. Besides the fact that the empty binary is ambiguous when indexing (it is taken to mean undefined), we have the following:

rhc:get_index(C, <<"bucket5">>, <<"i1_bin">>, {<<"#">>, <<"#">>}, []).

=ERROR REPORT==== 11-Aug-2015::15:46:34 ===
Error in process <0.57.0> with exit value: {{badmatch,{"application/json",[]}},[{rhc_index,index_acceptor,3,[{file,"src/rhc_index.erl"},{line,108}]}]}

In this case the URL generated is "http://127.0.0.1:10018/buckets/bucket5/index/i1_bin/#/#?stream=true", which is obviously wrong as the hash has a special meaning.