Integrate more cmake generators into the configure script
cmake can generate xcode projects, eclipse projects, visual studio projects, and whatnot. Currently we're just using the makefile backend. The alternatives should be advertised in the readme somewhere and also be provided by ./configure conveniently.
I'm not sure about the ./configure thing; after all, ./configure is there to provide autotools-like usage.
I'm just thinking the ./configure is our cmake helper. When using cmake directly, one can use -G eclipse and it'll generate the project files. This could also be supported by configure, e.g. ./configure --output xcode or something. The standard makefile-generation will be maintained of course.
I think people who like to use GUIs like eclipse, or even Visual Studio, will simply use the cmake GUI...
But of course, additional features that don't get in the way of existing ones are a plus most of times.
I added ninja support in #723