Fix plfs.spec file and some compile errors for the unittest tool

Remove the YAML library files, now they will be included in the
PLFS library directly.

Fix the mis-match types between the unittest tool and small file
and some compiler warnings.
Merge pull request #279 from zhang-jingwang/master

Fix plfs.spec file and some compile errors for the unittest tool
Merge branch 'master' of github.com:plfs/plfs-core
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