pkcs11-tool: ignore CRYPTOKI_ALREADY_INITIALIZED error

https://github.com/OpenSC/OpenSC/pull/118
Print warning and ignore 'Cryptoki library has already been initialized'  error
returned by C_Initialize().
pkcs15: new 'data' member in 'sc_pkcs15_data_info'

New member keeps the value of the PKCS#15 DATA object.

Internal pkcs15 procedure that reads DATA object is modified
to check if requested data are already vailable in 'data-info',
an only then try to read the content of dedicated on-card file.

For some emulated PKCS#15 systems value of DATA object is kept as 'direct' value
in a proprietary attribute files and so the common read procedure could not be used.

; some efforts to unify layout of code source.
pkcs15init tool: throw error when invalid appliaction-id supplied

fix action labels
pkcs15init: copy DATA object value to 'pkcs15-data-info'

When creating new DATA object, keep it's value in 'data' member of
'sc-pkcs15-data-info' data.
Used by pkcs15init emulation layer to store DATA value into a proprietary placement.
pkcs11: segfault if 'application-file' not defined

for some cards with emulated PKCS#15 'file_app' from 'application-info' is not defined
Normalize SC_ERROR_* API and clean up ISO7816-4 errors.

 * iso7816_check_sw() emits a "informational message" (from ISO7816-4 table 6)
 * SW-s which are not known or not meaningful for internal API get translated
   to SC_ERROR_CARD_CMD_FAILED by default, so use it also in the SW table
 * Remove undefined SW-s and move generic SW-s to their sequential location.

This commit improves 8fc679bf4062bc1d74092ed51eab663620dabaef
pkcs11: report the library version based on plug-n-play feature.
pkcs11: Don't touch readers or inserted cards in C_Initialize in 2.20 mode

This significantly speeds up calling C_Initialize.
Thanks to Nikos Mavrogiannopoulos for the tip.
pkcs11: use calloc instead of malloc; remove obsolete malloc.h references.
build: check for dlopen() in a BSD-friendly way.

From http://www.flameeyes.eu/autotools-mythbuster/autoconf/finding.html
build: remove useless svnignore file
build: svnignore went away in previous commit
pkcs15: 'issuer' and 'subject' have to be DER encoded sequence

'issuer' and 'subject' data have been the non-encoded sequence of rDNs