Land b_release_1_4_4 onto b1_4 (20050810_0211)

Land b_release_1_4_4 onto b1_4 (20050810_0211)
Description: Heavy concurrent write and delete load may cause data corruption.
Details    : It was possible under high-load situations to have an extent
             metadata block in the block device cache from a just-unlinked
             file overwrite a newly-allocated data block.  We now unmap any
             metadata buffers that alias just-allocated data blocks.
b=6998

Description: lconf+mke2fs fail when formatting filesystem with > 77 stripes
Details    : lconf specifies an inode size of 4096 bytes when the default
             stripe_count is larger than 77.  This conflicts with the default
             inode density of 1 per 4096 bytes.  Allocate smaller inodes in
             this case to avoid pinning too much memory for large EAs.
b=7241