prepare for v3

fix if structure contains slice inside, but the items in the internal…

… slice are not in the same order give wrong result (r3labs#82)

fix example test and check if identifier call is for struct

fix: slice index patch (r3labs#79)

fix: update to nil pointer (r3labs#78)

fix: add map with pointer value support (r3labs#76)

fix patching nil values

fix pointers when convert types is enabled

fix patch assignment to pointer values

safely interface reflect values (r3labs#70)