Increase rate limit for execute_query

[aaccomazzi]

When viewing search results from a bigquery, one easily hits the maximum limit apparently due to the fact that each facet query counts against execute_query. So 100 queries per day is way too small a limit, we should set this to be at least 5000.

{
 "error": "TOO MANY REQUESTS",
 "errorCode": 429,
 "destination": "vault/execute_query/0266c70541ae6b94365db350d6ef073b",
 "query": {
  "fq": [
   "{!type=aqp cache=false cost=150 v=$fq_author}",
   "{!type=aqp v=$fq_database}"
  ],
  "fq_author": [
   "(author_facet_hier:\"0/Murray, S\")"
  ],
  "q": [
   "*:*"
  ],
  "__qid": [
   "0266c70541ae6b94365db350d6ef073b"
  ],
  "fq_database": [
   "(database:physics)"
  ],
  "__database_fq_database": [
   "AND",
   "database:physics"
  ],
  "facet": [
   "true"
  ],
  "facet.field": [
   "author_facet_hier"
  ],
  "facet.mincount": [
   "1"
  ],
  "facet.limit": [
   20
  ],
  "facet.prefix": [
   "1/Accomazzi, A/"
  ],
  "fl": [
   "id"
  ],
  "facet.offset": [
   0
  ]
 }
}