Compiling with platformio cli

[Kilill]

Just a suggestion for the platformio build instruction.

Since i usually just use the platform io cli from a console the instructions for compiling and and uploading from the command line.
it of course presupposes that the platform cli is available , preferably also included in the PATH env variable...

Compile source
pio run
Build file system from data directory
pio run -t buildfs
Upload code image
pio run -t upload
Upload filesystem image
pio run -t uploadfs