Fix some AAE dialyzer errors

This commit fixes all the dialyzer errors for `riak_kv_entropy_info`
as well as an error for `riak_kv_exchange_fsm`.  The main change was
to fix the spec for `#index_info.repaired` which is actually a
`#simple_stat{}` not a `pos_integer()`. However, even after that
dialyzer was not happy with the explicit default values of `undefined`
without corresponding entries in the type definition. This seemed like
a waste to me given that Erlang will implicitly default records values
to `undefined` and insert the appropriate type spec. This is discussed
in the following reference manual:

http://www.erlang.org/doc/reference_manual/typespec.html#typeinrecords

Here is the full list of dialyzer errors which have been fixed:

```
riak_kv_entropy_info.erl:78: Function exchange_complete/4 has no local
return
riak_kv_entropy_info.erl:83: Function exchange_complete/5 has no local
return
riak_kv_entropy_info.erl:84: The call
riak_kv_entropy_info:update_index_info({_,_},{'exchange_complete',_,_,_})
will never return since it differs in the 2nd argument fr
riak_kv_entropy_info.erl:161: Record construction
repaired::pos_integer() and last_exchange::{non_neg_inte
riak_kv_entropy_info.erl:194: The call
riak_kv_entropy_info:update_simple_stat(Repaired::'undefined' |
pos_integer(),pos_integer()) will never return since it differs in
riak_kv_entropy_info.erl:208: Function compute_exchange_info/4 has no
local return
riak_kv_entropy_info.erl:218: The call
riak_kv_entropy_info:stat_tuple(Repaired::pos_integer()) will never
return since it differs in the 1st argument from the success t
riak_kv_entropy_info.erl:225: Function update_simple_stat/2 has no local
return
riak_kv_entropy_info.erl:225: The pattern <Value, 'undefined'> can never
match the type <'undefined' | pos_integer(),pos_integer()>
riak_kv_entropy_info.erl:227: The pattern <Value, Stat = {'simple_stat',
_, Min, Max, Cnt, Sum}> can never match the type <'undefined' |
pos_integer(),pos_integer()>
riak_kv_entropy_info.erl:234: Function stat_tuple/1 has no local return
riak_kv_entropy_info.erl:234: The pattern 'undefined' can never match
the type pos_integer()
riak_kv_entropy_info.erl:236: The pattern {'simple_stat', Last, Min,
Max, Cnt, Sum} can never match the type pos_integer()
riak_kv_exchange_fsm.erl:379: Function exchange_complete/4 has no local
return
```
Fix dialyzer error in kv_mrc_map

This was uncovered once basho/riak_pipe
a33ac811ddefff0f0a9c04cbec4611a1537ed98a was committed.
Merge pull request #941 from basho/bugfix/pipe-worker-init-spec

Fix dialyzer error in kv_mrc_map

Reviewed-by: seancribbs
riak_kv_env:doc_env/0 handles the case of an erlang that doesn't support
 erlang:system_info(ets_limit)
Merge pull request #942 from basho/bugfix/jnd/everybody-to-the-limit

Better error handling from basho/riak_kv#935

Reviewed-by: reiddraper
Comment out get_put_monitor_eqc property

The get_put_monitor_eqc property exhibits nondeterministic failure on
certain machines and is preventing unrelated work from being
merged. Comment out the test temporarily until the failure can be
resolved or the test can be replaced.
Merge pull request #945 from basho/comment-out-get-put-monitor-property

Comment out get_put_monitor_eqc property

Reviewed-by: reiddraper
Merge pull request #924 from basho/rz/entropy-info-dialyzer-fixes

Fix some AAE dialyzer errors

Reviewed-by: reiddraper
Remove dialyzer warnings fixed by core change

This is fixed in basho/riak_core#577
Merge pull request #920 from basho/bugfix/920-remove-dialyzer-ignores

riak_core_security:check_permission/2 usage

Reviewed-by: reiddraper