Fix constraints on from_json(CompatibleArrayType)

Fixes #924

Make coveralls watch the include folder

Add a note about installing the library with cget

Added out_of_range exception for UBJSON containers with sizes that exceed the target container's max_size.

Beside the fix discussed in #961, we also had to re-adjust a test case. It seems that it was failing before, and I "fixed" it to work with the broken implementation...

Fix links in README.md

- updated documentation wrt. new repository layout
- temporarily switched off Homebrew --HEAD building (can only be switched on after release)
- set copyright date to 2018

fix cmake install directory (for real this time)