Fixes#1164 and thus also #1150, #1149, #1147 and #898.
* Move to latest version of SPIFFS
* Add SPIFFS porting layer for NodeMCU
* Add option to delete output if it doesn't fit
* Change FLASHSIZE to be in bits by default: default 4mb 32mb
* Add SPIFFS_MAX_FILESYSTEM_SIZE override
* Add notes on SPIFFS_FIXED_LOCATION
* Add 1M boundary
* Include the current version of the LICENSE
Also made the cache on/off configurable via user_config.h. Uncached writes
are not a very good idea, but for read-only deployments a further ~0.5k RAM
can be gained by disabling the cache.
Tweaked the file.read() workhorse to read large chunks at a time rather
than use getc(), to compensate for potential unavailability of cache.
sergio
Philip Gladstone
Johny Mattsson
funshine