Updated read me to point to tinker for examples. (bunq/sdk_java#81)

[OGKevin]

References #81

[OGKevin]

@patrickdw1991 please 👓

[patrickdw1991]

The links you use aren't really nice, the problem would be that if you update the tinker repo you might also need to update the readme to fix the links (and point them to the newer versions of the example files)

[OGKevin]

@patrickdw1991 yes that is intended, as if tinker changes and the code line shifts ore something these links must be updated. Its is better to link to something good as of the user landing on random lines in tinker that has nothing to do with the example :P.

[OGKevin]

@andrederoos