Add possibility to get length and other information of EC based
certificates. Also it is possible to parse those public/private
keys from PEM and DER encoded files.
Based on patch by Remco Bloemen
[ChangeLog][QtNetwork][SSL/TLS support] It is now possible to
parse elliptic curve certificates.
Change-Id: I4b11f726296aecda89c3cbd195d7c817ae6fc47b
Task-number: QTBUG-18972
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
