Filearray 0.1.3

• Automatically detect whether symbolic-link works and show warnings
• Warnings can be suppressed
• Allow extra headers to be set in meta file
• Added header signature method
• Fixed symbolic-link issues on Windows when partition sizes are 0
• Added check-load function filearray_checkload to validate header
• Fixed collapse method when dimnames are set
• Fixed an unprotected variable in C++ code
• filearray_bind can use cache if the header signatures agree
• filearray_bind can choose to force overwrite
• Added package digest to Imports
• Fixed a typo and several small bugs