e-vcard: Fix a minor memory leak for multi-valued parameters

(cherry picked from commit 26eb7865458c59d38c82efb853611f9e7250cb3d)
e-vcard: Fix case sensitivity of string comparisions

The rest of the code (and the specification) uniformly users
case-insensitive comparisons of attribute names and parameter values.

(cherry picked from commit 88240da1b6e1c39801c4de19d91e79dee205d842)
Bug 712323 - Substantially expand EVCard documentation

(cherry picked from commit f508b03403e89d4484892b3b2a2dd5be1ac534ca)