allow Elektra to be compiled using mingw

fix cmakedefine
fix usage of HAVE_STDIO_H
split moremeta things (that are likely to move to a seperate library)
(and exclude it for WIN32)
exclude array and ksLookupBySpec for WIN32 (64bit not available?)
only add dependency from kdb-static to resolver-lock if needed
no environ for WIN32
allow Elektra to be compiled using mingw

fix cmakedefine
fix usage of HAVE_STDIO_H
split moremeta things (that are likely to move to a seperate library)
(and exclude it for WIN32)
exclude array and ksLookupBySpec for WIN32 (64bit not available?)
only add dependency from kdb-static to resolver-lock if needed
no environ for WIN32
add a screenshot
remove modeltests and fix link to libelektra.org
Merge 'qtgui' 0.0.1 alpha

See https://github.com/ElektraInitiative/libelektra/pull/129
fix documentation regarding key meta

- explain reference counting
- fix links in keyNew
- make old meta data obsolete in keyNew
- add xdg_bds to be used for XDG resolving
add example how different ordering could be done in c++
added parallel tester
use nanosecond precision in resolver
fix protocol to update timestamp of file

(+ compiles again)
Merge remote-tracking branch 'upstream/master'