Added support for getdtablesize.
Merge branch 'master' into add-getdtablesize

Conflicts:
	src/main/java/jnr/posix/LibC.java
POSIX#close
Merge pull request #18 from akiellor/add-getdtablesize

Added support for getdtablesize.
Merge pull request #20 from akiellor/close

POSIX#close