Better error message for variables without ? #476

1. Unhandled xyz.triplox.client.TriploxException
   EDN parse error: error at 1:17: expected one of ".", "/", ['+' |
   'a'..='z' | 'A'..='Z' | '0'..='9' | '*' | '!' | '_' | '?' | '$' |
   '%' | '&' | '=' | '<' | '>' | '-'], expected variable

          TriploxNode.java:  197  xyz.triplox.client.TriploxNode/sendAndCheck
          TriploxNode.java:  181  xyz.triplox.client.TriploxNode/postBinary
          TriploxNode.java:   80  xyz.triplox.client.TriploxNode/ ....