Merge branch 'release-1.2' into develop
change buffer size

was initially this big because the same buffer was used
for buffering I/O too.
testing existence of files prior to compare timestamps
comment .gitignore
chang .gitignore for MacOSX
add XCode project file
inlining
change version for 1.2.1
update README

compatibility note + typo
Merge branch 'release-1.2.1'