CBQE-812: Random values for templates

- Enter datatype as the value in the key value
pairs
- Permitted data types (supporting magic ints/strings)
	$lis,$dic,$boo,$int,$flo,$str
- Also permits user defined generator, enter as:
	<module_name>.<class_name>.<method_name>([argument])
- Supported sample:
	--kvpair '"email":"$str10@couchbase.com" '
		 '"city":"$str5"'
  		 '"list":["$int1","$str1","$flo1"]'
 		 '"map":{"sample" : "$str3", "complex" : "$flo1", "val" : "$int2"}'
		 '"num":"$int"'
		 '"flo":"$flo"'
 		 '"st":"$str"'
		 '"li":"$lis"'
		 '"di":"$dic"'
		 '"b":"$boo"'

Change-Id: Ie87258c866483c9b39e05ef8d77eb8589c7d7f88
Reviewed-on: http://review.couchbase.org/23429
Reviewed-by: Tommie McAfee <tommie@couchbase.com>
Tested-by: Tommie McAfee <tommie@couchbase.com>