blk: update checksum calculation algorithm

- Update the checksum handling to handle BE systems.
- Improve the way the chk-sums are calculated.
- Adjust the checksum unittest to be endianess aware.

Initial version by @mdalecki
Merge pull request #57 from tomaszkapela/pmemblk_checksum_update

blk: update checksum calculation algorithm
vmem: fix possible attempt to unlock a mutex that is not locked
Merge pull request #58 from krzycz/vmem-ctl_mtx_unlock

vmem: fix possible attempt to unlock a mutex that is not locked
vmem: fix race condition in chunk_alloc_default()

Protect "pool->arenas" with "pool->arenas_lock".
Move the call to chunk_recycle() outside chunk_alloc_core(),
because the lock is needed only when (pool->pool_id == 0).
Merge pull request #59 from ldorau/vmem-fix-race-condition-in-chunk_alloc_default

vmem: fix race condition in chunk_alloc_default()
doc: updated example for libpmem man page
common: fix typos
doc: reflect library reorganization

All man pages now match the intended library reorganization.
Since some of the examples are used to create the man pages,
they've been updated ahead of the rest of the tree and therefor
building all the examples is currently disabled to prevent build
failures.
obj: minor typo in example
common: add manpages to pkg scripts

- add manpages to pkg scripts
- uncomment running tests
Merge pull request #61 from plebioda/add-manpages-to-pkg-scripts

common: add manpages to pkg scripts
blk: finish the implementation

- Recover from failed flog map updates.
- Handle wrong block sizes during opening of pools.
- Add invariant checks inside btt where appropriate.
- Remove unnecessary callback entry point

Initial version by @mdalecki
Merge pull request #60 from tomaszkapela/pmemblk_finish_impl

blk: finish the implementation
pmem: split pmem_pool_open into pmem_pool_create and pmem_pool_open
Merge pull request #62 from krzycz/pmem-pool_create

pmem: split pmem_pool_open into pmem_pool_create and pmem_pool_open