Improve printout of elvis_core errors from config validation. #75
Description
If my elvis.config file is invalid, this happens…
% rebar3 lint
…
===> elvis analysis starting, this may take a while...
===> elvis_core threw an exception: {invalid_config,
[105,110,32,39,101,108,118,
105,115,46,99,111,110,102,
105,103,39,44,32,97,116,32,
108,105,115,116,32,112,111,
115,105,116,105,111,110,32,
110,117,109,98,101,114,32,
"1",44,32,105,110,32,39,100,
105,114,115,39,44,32,116,104,
101,32,102,111,108,108,111,
119,105,110,103,32,101,108,
101,109,101,110,116,115,32,
97,114,101,32,110,111,116,32,
40,111,114,32,100,111,110,39,
116,32,99,111,110,116,97,105,
110,41,32,100,105,114,101,99,
116,111,114,105,101,115,58,
32,"[\"apps/**/src\"]",46]}