Start 2.2.28 Development Cycle: POSTPONE and DEFER

About the Pre-Release

This release is going to modernize eForth by introducing some Forth-Standard words.

fixes #409: work around for STM8L151 serial bootloader erratum

fixes #411: add ['] and DEFER ... IS
#411 add test for DEFER ... IS and [']

fixes #413 POSTPONE supersedes COMPILE and [COMPILE]
fixes #413 POSTPONE supersedes COMPILE and [COMPILE]

fixes #414 implement POSTPONE
#414 add test for POSTPONE
#414 make COMPILE and [COMPILE] replaceable with ALIAS to POSTPONE

#416 some minor core optimizations
#416 some minor core optimizations
#416 more compact CALL,

fixes #417 use COMPILIT instead of COMPILE in core

fixes #419 use POSTPONE in lib
#419 use POSTPONE in >REL
#419 use POSTPONE in [']
#419 use POSTPONE in ALIAS
#419 use POSTPONE in DEFER
#419 use POSTPONE in :NVM
#419 use POSTPONE in S"
#419 use POSTPONE in EVALUATE
#419 use POSTPONE in CONSTANT
#419 use POSTPONE in MARKER
#419 use POSTPONE in VOC
#419 use POSTPONE in VOCABULARY

fixes #420 incorrect TIB constant export
#420 incorrect TIB constant export

#421 codeload.py: less restrictive line length check