Fix strict aliasing issue/warning

For the levels 2 and 3 of the -Wstrict-aliasing flag,
gcc (4.6.3) emitted the following warning:

src/node_types.h: In function 'decode_kv_length':
src/node_types.h:81:5: warning: dereferencing type-punned pointer will break strict-aliasing rules [-Wstrict-aliasing]

Which is dangerous since by default we compile with -O2.

Change-Id: Ibffc6a4188715a7562d14bfd8d83e0843ab606d6
Reviewed-on: http://review.couchbase.org/24159
Reviewed-by: Fulu Li <fulu@couchbase.com>
Reviewed-by: Aaron Miller <apage43@ninjawhale.com>
Tested-by: Aaron Miller <apage43@ninjawhale.com>
Tested-by: Filipe David Borba Manana <fdmanana@gmail.com>
Fix implicit pointer to integral type cast

From gcc:

src/db_compact.c:87:5: warning: passing argument 3 of 'couchstore_compact_db_ex' makes integer from pointer without a cast [enabled by default]
src/db_compact.c:40:20: note: expected 'uint64_t' but argument is of type 'void *'

Change-Id: I9326c2bb4ff639fca995f1de4c0f5fe5172c11a1
Reviewed-on: http://review.couchbase.org/24162
Reviewed-by: Fulu Li <fulu@couchbase.com>
Reviewed-by: Aaron Miller <apage43@ninjawhale.com>
Tested-by: Aaron Miller <apage43@ninjawhale.com>
Tested-by: Filipe David Borba Manana <fdmanana@gmail.com>
Merge remote-tracking branch 'origin/2.0.1'

* origin/2.0.1:
  Fix implicit pointer to integral type cast
  Fix strict aliasing issue/warning

Change-Id: I476ab04812ec98b8283cbb11e9423bfa4724dc5d