quagga: add from OE-Classic, update and tidy-up

quagga: add from OE-Classic, update and tidy-up

* Update to 0.99.21
* Fix SRC_URI to point to a working download location
* Make LICENSE more accurate
* Add LIC_FILES_CHKSUM
* Add old gentoo patch to fix libcap linking errors
* Put binaries in sbindir
* Use useradd.bbclass to create user/groups
* Handle hardcoded paths in initscript
* Add LSB headers to initscript (borrowed from debian)
* Tidy up packaging and directory references
* Add SUMMARY

(From meta-openembedded rev: e762ce3fc044cc64f473c95e096245e439eb3234)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>