index_entry: Added missing fields.

This adds dev, ino, mode, uid, gid, file_size, oid, flags, and flags_extended, which were previously omitted.

Fixes #94.
Regenerated include/index_entry.h and src/index_entry.cc after new fields were added.
Merge pull request #95 from papandreou/addMissingFieldsToIndexEntry

Add missing fields to index entry
new add and remove file example
cmake 2.8 is required to build nodegit

The "--build" option appeared in 2.8, some distros such as rhel provide cmake 2.6 by default and it can take a while to figure why the build fails.
Merge pull request #100 from dcolens/patch-1

cmake 2.8 is required to build nodegit
Fixed method names in reference example

fixes #98
Fixed wrong variable name.
Fixed unknown oid for general examples
Fixed unknown commit oid
Merge pull request #99 from dcolens/master

new add-and-commit.js and remove-and-commit.js examples
Changed default value of working dir to a existing git folder
Merge pull request #102 from micha149/example-fixes

Reviewd and fixed examples
Changed v0.18.0.json so diffWorkDir DiffOptions argument is optional. Added .idea to .gitignore to support webstorm.
Updated v0.18.0.json to make the index and DiffOptions arguments in tree.diffIndex optional (libgit2 supports null for both)
Merge pull request #103 from kciccarello/master

Changed v0.18.0.json so diffWorkDir DiffOptions argument is optional. Ad...
Updated v0.18.0.json to make the index and DiffOptions arguments in Index.indexToWorkdir optional (libgit2 supports null for both)
Duplicate git_error before passing it on as it will cross a thread boundary.
Regenerated sources.
Merge pull request #106 from kciccarello/master

Updated v0.18.0.json to make the index and DiffOptions arguments in Inde...