Asynchronous storage.

• Asynchronous writes to disk.
• Asynchronous memory storage.
• PageManager: drop loaded chunks (on get_open_chunks) and dec chunks_in_cur_page() counter.
• PageManager: page fragmentation support.
• Chunk memory pool.

write speed up

• spinlocks in memory cache.
• B+tree based caches
• flush data on write to page
• write speed: 3 millions measurement per second in 5 threads.

v0.0.3: Merge pull request #58 from lysevi/dev

• refactoring
• more tests
• memory usage
• speed up

single file storage.

v0.0.2

comment.

memory storage.

Merge pull request #35 from lysevi/battle

speed up and benchmarks