Change all occurrences of value to pointer receivers
Add meta sys files to .gitignore
Code cleanup e.g.
- Don't capitalize error statements
- Fix ignored errors
- Fix ambiguous variable naming
- Remove unnecessary type casting
- Use named params
Fix#306
* shrink the value type
went down from 40 bytes to 24
* add missing license blurb
* stringify value type
* print string value types in stdout exporter
* make Value function take a pointer receiver