v0.3.3 : Fixes

fw_printenv: dont hard-code configuration/environment files
fw_setenv: fix bug when SPI flash write size != sector size
uboot_env: fix fileprotect for Android
CI: add REUSE compatibility check
Android.bp: add missing copyright
Android.bp: initial addition
uboot_env: remove unused function
uboot_env: remove unused parameters
uboot_env: remove unused variables
uboot_env: fix pointer-sign warnings
uboot_env: switch to strchr/strrchr
Add description of the fw_setenv script syntax
Include cstddef in the header for C++
Correct type of conversion of HEX .flags
Fix parsing multiple .flags variables
Add REUSE badge
Make libubootenv REUSE compliant
doxygen: fix libuboot_open/close return value description
Add documentation for the configuration file
Add configuration for disabling MTD lock
main: Remove duplicated code about '=' in variable name.
libubootenv: Forbid to give empty variable name to fw_setenv.
main: Check libuboot_set_env() result.
CI: add gitlab config