- Move __gcov_flush to process_spawn, for more reliable coverage
tracking of subprocesses
- Travis: use GCOV_ERROR_FILE
- codecov: use "-X fix" to skip "fixing" uploaded coverage data; it
should be handled by codecov's backend instead.
- AppVeyor: no $PATH mangling, which breaks with the improved coverage tracking
due to missing .dll in PATH.
* Add ci/common/submit_coverage.sh, used with Travis and AppVeyor
* use gcovr, with coverage.xml for better branch coverage reporting, and
easier processing of gcov files in general
* codecov: use flags again, with `uname -s` additionally
Ref: https://github.com/neovim/neovim/pull/10227#issuecomment-502923543
* remove now unused parsers.gcov config from codecov.yml
