Basic support for EAC documents (e.g. German Identification Card)

-new files armsrc/epa.[ch] for ePA (electronic "Personalausweis") related functions
    -Offers elementary functions (EPA_PACE_MSE_Set_AT etc.)
    -Also offers one new USB command: EPA_PACE_Collect_Nonce
-created new command subtree in client: client/hfepa.[ch] ("hf epa")
    -offers "hf epa cnonces" (collect encrypted PACE nonces)
-more to come

client/Makefile

@@ -56,6 +56,7 @@ CMDSRCS = \
 			cmdhf14a.c \
 			cmdhf14b.c \
 			cmdhf15.c \
+			cmdhfepa.c \
 			cmdhflegic.c \
 			cmdhficlass.c \
 			cmdhfmf.c \