Update installation.rst
add docker & vagrant files
Merge pull request #8 from spreeker/master

pep8, s7util fixes due to client change.
Update CHANGES
move s7util to util, fix travis
Update README.rst

added link to youtube movie.
Fix for OSX x86_64 libsnap7
Allow init Snap7Library with library path

Also avoid reloading the lib on multiple calls, since __init__ is
always called even for the singleton pattern used here.
Add option to start server passing lib path
Merge pull request #10 from lkraider/master

Fix for OSX x86_64 libsnap7
add gitter
convert markdown to rst
add manifest file, new release
prevent writing data to read only part of spec
add row_offset, to add more write protection
add key checking, ignoring empty rows
assert were dealing with ints/dwords when setting one
better check parameters when setting data