Textformats

- Documentation:
- fix some README file links
- improve structure of CHANGELOG

- Python packaging:
- now compilation on MacOS arm64 works

- Pre-compiled specifications:
- tfs files can now be read from stdin
- tf_spec compile accepts tfs specs in input
(output is equal to the input)

- Example applications:
- GFA1 example was implemented in Nim

- Python packaging
- new own build system (not based on nimporter)
- works for both source and binary distributions

- Performance improvements
- improve handling of as_string optional key
(avoid downstream parsing if regex matches)

- Pre-compiled specifications:
- avoid unnecessary operations on reference restoring
- implement TFS files as msgpack
(previous TFS files are incompatible)

- Documentation:
- great improvement of README file

- Performance improvements:
- avoid nested exception handling
- branch prediction in union datatypes decoding
- use refc GC (was markAndSweep)

- Newer library/compiler versions:
- use Nim 1.6 (was Nim 1.4)
- use regex 0.19 (was 0.18)

- New example applications and benchmarks:
- SAM: generate larger data for benchmarks
- GFA1: show how to fix invalid data output
by another application
- GFA2: gfa2_info script implemented in
Python with TextFormats and
with gfapy (for comparison)
- EGC: compare to Python ad-hoc parser;
compare Python to Nim and C;
generate large benchmark data
- GFF3: data conversion from custom
tabular annotation data

- Build system:
- make clear requirements in nimble file
- support newer versions of NimYAML and regex libraries
- automatically find nimbase.h in C Makefiles
- make sure nimporter==1.0.2 is installed when installing Py module

- Documentation:
- add this changelog file

Initial release