fixed #1401 build fixed on FreeBSD

git-svn-id: http://sphinxsearch.googlecode.com/svn/trunk@3616 8b96e2b9-35c5-2c16-bc47-5122d61876d4
fixed outer limit check; cleaned up C-style comments

git-svn-id: http://sphinxsearch.googlecode.com/svn/trunk@3617 8b96e2b9-35c5-2c16-bc47-5122d61876d4
outer order clause is now optional (copied from inner one if unspecified)

git-svn-id: http://sphinxsearch.googlecode.com/svn/trunk@3618 8b96e2b9-35c5-2c16-bc47-5122d61876d4