Under WSL, Python in text mode will translate `\n` into `\r\n`, even
though other tools and utilities use `\n` (because WSL is basically
Linux). This leads to the update scripts leaving the files with
Windows newlines even though git and similar expect them to have
Linux newlines.
By instead handling files in binary mode, we can keep the original
newlines. This commits switches parts of the update process to
binary mode, but not all because some of the will require a lot of
work to fix.
This also goes for pkg-config installed by our CMake installation.
This includes
* Updating CMake version on Travis
* Adding a `Catch2` subfolder to the `single_include/` folder to
provide this include path both _inside_ the repository, and _outside_.
* Updated examples to build with the new paths
* Other general CMake cleanup
as prompted by #365, #430, #447 and a thread on the google group.
- split version bumping out of generateSingleHeader script
- separate scripts for bumping each version component
- "build" number only incremented for "develop" builds
