TwitterBridge: partial merge of id_str usage from 0.9.x for improved 32-bit and pre...

TwitterBridge: partial merge of id_str usage from 0.9.x for improved 32-bit and pre-5.2.10 compatibility. (on 64-bit in 5.2.6 we can pull the integer IDs, but silently lose some precision on the end.)

Fixes for Twitter bridge breakage on 32-bit servers. New "Snowflake" 64-bit IDs have become too big to fit in the integer portion of double-precision floats, so to reliably use these IDs we need to pull the new string form now.
Machines with 64-bit PHP installation should have had no problems (except on Windows, where integers are still 32 bits)

Conflicts:

	plugins/TwitterBridge/twitterimport.php <- as this hasn't been broken out, the import code is NOT FULLY UPDATED HERE.