new dimension handling and broken primitve parsers
embryonic management of TeX registers
a new bunch of (really simple) parsers

then will then be used to parse \if* primitives to expand or then to
parse typesetting commands
new parser infrastructure
a lot of stuffs
fix parser
first complete TeX lexer with token positions
fix alternative operator
add label to parser for better error messages
add stream processor

special kind of parser that allows to process lazy streams
add some lexer tests
can choose parser for building streams
more hints in lexer
update test to match new stream processor
new way to handle position
new parsers
improve parser

we are now able to parse macro definitions
parser enriched

the first draft for macro expansion now exists
environment improved

now that a TeX environment is quasi) immutable, we don't need to have a
nested environment class, as each nesting level has its own environment
instance
enriched parser with more expansion