Improving ci.coords doc

Conflicts:
	man/pROC-package.Rd
Warn before allocating more than about 1GB in DeLong.

Conflicts:
	R/cov.R
	R/var.R
Update doc

Conflicts:
	man/pROC-package.Rd
Forgot to export print.ci.coords
Executing some minimal examples in ci.coords
Merge branch 'master' into parallel

Conflicts:
	man/pROC-package.Rd