Add .gitignore for C
Add usefull common functions not in C standard
Add low level communication functions, aka influxdb_client
Add API functions for database management
Add API functions for cluster admin management
Regardless return callback type of json list extractor
Add API functions for cluster management
Add API functions for database users management
C89 compatibility
Add API functions for series usage
In client: path can contain ?smth, user and password are correctly added
Add query (send and retrival) management
Add global include file
Add compile chain
Update README
Add ping request
Add continous query management
Coherent improvement
Add shard management
Fix stack smashing