v_eval 0.3.0

Expression evaluator with context
Documentation
# CHANGES

## [0.2.0] XXXX-XX-XX

### Added
- Add Str, Range, Vec<Value> Values 

## [0.1.0] 2019-09-08

### Updated
- Bump syn and quote version to `1.0`

## [0.0.2] 2019-03-18

### Fixed

- Fix operation preference on variable 
- Document and prettify

## [0.0.1] 2019-03-18

### First release