Better readme file, with small example.
Better readme file, with small example.

- better formating, with Markdown style
- small/clean extract of the examples in main.cpp

sergiosvieira/SQLiteCpp,PSPDFKit-labs/SQLiteCpp,hongshibao/SQLiteCpp,mc-server/SQLiteCpp,CHUYilei/SQLiteCpp,CHUYilei/SQLiteCpp,SRombauts/SQLiteCpp,SRombauts/SQLiteCpp,CHUYilei/SQLiteCpp,layerhq/SQLiteCpp,SproutOrc/SQLiteCpp,SproutOrc/SQLiteCpp,PSPDFKit-labs/SQLiteCpp,sergiosvieira/SQLiteCpp,sndnvaps/SQLiteCpp,hongshibao/SQLiteCpp,hongshibao/SQLiteCpp,layerhq/SQLiteCpp,bmildner/SQLiteCpp,bmildner/SQLiteCpp,mc-server/SQLiteCpp,SRombauts/SQLiteCpp,bmildner/SQLiteCpp,bmildner/SQLiteCpp,sergiosvieira/SQLiteCpp,CHUYilei/SQLiteCpp,sndnvaps/SQLiteCpp,stelalae/SQLiteCpp,layerhq/SQLiteCpp,SproutOrc/SQLiteCpp,layerhq/SQLiteCpp,sndnvaps/SQLiteCpp,PSPDFKit-labs/SQLiteCpp,mc-server/SQLiteCpp