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
* use strconv instead of fmt.Sprint
* rollback float it has no significant improvement on time and worse allocated bytes.
* change int32 and uint32 to separate cases.
* 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
This is to shrink the PR #100.
The only place where the registry.Variable type was used was metrics,
so just inline that type into its only user. The use of the
registry.Variable type in core.Key was limited to the Name field.
The stats package also used the registry.Variable type, but seems that
also only the Name field was used and the package is going to be
dropped anyway.