Hunt Framework 2.1.0 released

[zoujiaqing]

## Hunt Framework 2.1 Changelog

### Hunt library
The Hunt module is enhanced, the API is richer, friendlier and 
more stable, and the I/O performance and stability are further 
improved. We are trying to improve the modules such as hunt. 
Concurrency, Locale, hunt. IO and hunt. Collection.

### For database
- **hunt-database**
Mainly fixed database connection pooling issues and now better 
supports high concurrent database requests.

- **hunt-sql**
Major enhancements include support for PostgreSQL statements.

- **hunt-entity**
Mainly fixed some bugs related to transaction processing and SQL 
statement generation.

### I18N APIs
1. New language dictionary data batch add interface;
1. The language dictionary lookup interface is changed from 
getText to trans.

### Other changes
1. Fix the problem that the view file may not be loaded correctly;
1. Fix Session storage problem;
1. Fix the problem of obtaining url query parameters;
1. JsonResponse module improvement;
1. Support direct use of Redis storage operation.

Github repository:
https://github.com/huntlabs/hunt-framework

Dub package:
https://code.dlang.org/packages/hunt-framework

HuntLabs homepage:
https://www.huntlabs.net