lib-charset: Added CHARSET_MAX_PENDING_BUF_SIZE macro and asserts for it.

lib-charset: Added charset_utf8_to_utf8_begin() wrapper function. It's never supposed to fail, so it makes it nicer for the callers who need to use it.

lib-charset: UTF-8 -> UTF-8 translation was never returning CHARSET_RET_INCOMPLETE_INPUT Instead the incomplete input was just being modified into broken output.

Replaced "decomposed titlecase" conversions with more generic normalizer function. Plugins can now change mail_user.default_normalizer. Specific searches can also use different normalizers by changing mail_search_context.normalizer.

Added more consts, ATTR_CONSTs and ATTR_PUREs. --HG-- branch : HEAD

Added charset_to_utf8_str() --HG-- branch : HEAD

Changed .h ifdef/defines to use <NAME>_H format. --HG-- branch : HEAD

charset_to_utf8_begin() API change. --HG-- branch : HEAD

Use uni_utf8_to_decomposed_titlecase() to have proper case-insensitive UTF-8 comparing. --HG-- branch : HEAD

Removed unused charset_to_utf8_string() and charset_to_ucase_utf8_string() --HG-- branch : HEAD

Removed CHARSET_RET_OUTPUT_FULL, it can't happen anymore. --HG-- branch : HEAD

charset_to_utf8() isn't used anymore, so renamed charset_to_utf8_full() to it. --HG-- branch : HEAD

_charset_utf8_ucase() -> charset_utf8_ucase_write(), _charset_utf8_ucase_strdup() -> charset_utf8_ucase_strdup() --HG-- branch : HEAD

charset_to_utf8_begin() now takes bool ucase parameter. Changed charset_to_ucase_utf8*() to charset_to_utf8*(). --HG-- branch : HEAD

Added charset_is_utf8() and charset_to_ucase_utf8_full(). --HG-- branch : HEAD

deinit, unref, destroy, close, free, etc. functions now take a pointer to their data pointer, and set it to NULL. This makes double-frees less likely to cause security holes. --HG-- branch : HEAD

Added "bool" type and changed all ints that were used as booleans to bool. --HG-- branch : HEAD

Naming style changes, finally got tired of most of the typedefs. Also the previous enum -> macro change reverted so that we don't use the highest bit anymore, that's incompatible with old indexes so they will be rebuilt. --HG-- branch : HEAD

Full not-too-well-tested support for SORT extension. Required a few library interface changes. --HG-- branch : HEAD

Don't use Buffers with read-only data, just makes it more difficult without gaining anything. --HG-- branch : HEAD

Compiles again without iconv() --HG-- branch : HEAD

Added buffer API. Point is to hide all buffer writing behind this API which verifies that nothing overflows. Much better than doing the same checks all around the code, even if it is slightly slower. Buffer reading is still mostly done directly, that isn't such a big security risk and I can't think of a reasonable API for it anyway. --HG-- branch : HEAD

SEARCH CHARSET now works properly with message bodies, and in general body searching works more correctly by decoding base64/qp data. Non-text MIME parts are currently not included in search, that could be made optional. Also the body is parsed separately for each keyword, that could be optimized. Changed base64_decode() behaviour so that it can accept non-base64 data as well, ie. line feeds etc. --HG-- branch : HEAD

SEARCH CHARSET support. Currently we do it through iconv() and only ASCII characters are compared case-insensitively. --HG-- branch : HEAD