* this should fix crashes reported in issue #497
* don't allow receiver thread to write directly into arbitrary main thread's memory
* instead use cmdBuffer[] for CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K as well
* add timeout and warning options to GetFromBigBuf(), same as in WaitForResponseTimeoutW()
* move GetFromBigBuf() from data.c to comms.c
* remove data.c and data.h
* change variable 'sp' from global to static
* move code to open and close USB port to comms.c (OpenProxmark() and CloseProxmark())
* change scope of USBCommandReceived() to static
* (flasher still unchanged)
* change variable 'offline' from global to static
* change variable 'FlushAfterWrite' from global to static
* remove unused global variable 'current_command'
* WaitForResponseTimeoutW(CMD_UNKNOWN, ...) waits for any command
* #include "printf.h" or <stdio.h> in iso15693tools.c to define sprintf()
* and some minor changes/comments
* move communication related code from proxmark3.c and cmdmain.c to new file comms.c
* replace byte_t by uint8_t in uart_posix.c and uart_win32.c
* move OpenProxmark() and CloseProxmark() from flasher.c to flash.c
* move print_lock mutex including initializer to ui.c
* minor changes in printing help texts
* no changes in comms functionality yet
to use lf config settings instead of it's own settings. (now allows
full options of lf config...)
also it will now run `data samples` when the command completes making it
not necessary to run manually...
note: adjusted client wait message as it was confusing.
* prevent WDT crash on repeated tries
* comes with faster execution as side effect
* use uint8_t instead of byte_t
* populate ar instead of (correctly) assuming that it is zero
* remove the "will take a few seconds longer" message because it is no longer true