work_queue_worker now listens for SIGCHLD correctly.

Added link_usleep_mask() that accepts a signal mask, unblocks any signal provided during the poll itself (it restores the old mask afterwards), and exits if EINTR is thrown.




git-svn-id: file:///afs/nd.edu/user37/ccl/svn/cctools/trunk@2695 a4d8336d-3463-0410-8bba-c098c45d37a8
Ignore files generated during compilation.

This decreases the frustration using git by hiding all of the files that
should not be committed to the repository.

The first step was to add the common files with obvious extensions e.g.
`.o`. Next I dumped the results of git status into `.gitignore` with
`git status | tail -n +5 | awk '{print $2}' | head -n 52 >> .gitignore`.

This file will need to be modified in the future if new compilation
units are introduced.
Merge pull request #1 from rampantmonkey/git_ignore

Ignore files generated during compilation.