add option to disable two-way binding

[Rich-Harris]

Alternative to #1056. Fixes #54

[codecov-io]

Codecov Report

Merging #1059 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1059      +/-   ##
==========================================
+ Coverage   92.02%   92.04%   +0.02%     
==========================================
  Files         121      121              
  Lines        4376     4538     +162     
  Branches     1410     1506      +96     
==========================================
+ Hits         4027     4177     +150     
- Misses        148      152       +4     
- Partials      201      209       +8

Impacted Files	Coverage Δ
test/parser/index.js	100% <ø> (ø)	⬆️
src/parse/state/tag.ts	96.07% <100%> (+0.05%)	⬆️
src/parse/index.ts	89.28% <100%> (+0.12%)	⬆️
src/validate/html/validateElement.ts	87.58% <0%> (-1.31%)	⬇️
src/generators/nodes/Text.ts	100% <0%> (ø)	⬆️
src/generators/dom/index.ts	96.42% <0%> (+1%)	⬆️
src/validate/index.ts	88.88% <0%> (+2.22%)	⬆️

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[Conduitry]

I'd been trying to organize the options in the readme into roughly conceptual sections. I think bind more belongs in the first section, which contains options to alter the behavior of the component or features in the compiled component.

[Rich-Harris]

Totally missed that! Updated