operator>> now works as expected.

Fixed to make sure no token is "overlooked".

Also added a Travis builder with -std=c++1z

fix doxygen error of basic_json::get()

Fixing assignement for iterator wrapper second, and adding unit test

Adding first and second properties to iteration_proxy_internal

Adding support for Meson.

Test cases succeed as expected, but the example in #367 is not fully
realized yet.

An optional parameter for dump() allows to set the character to use for
indentation (default: space). In case a JSON value is serialized to an
output stream, its fill character is used (and can be set with
std::setfill).

I forgot to consider the offset.

a simple acceptor function