Contribute an example with more libgit2 calls

[iliakan]

I'd like to contribute an example with multiple libgit2 calls, rather than single lg2 point of entry.
As of now, I have "git init" + "git add" working.

It needs more exports in build.sh,
something like this:

emcmake cmake -DCMAKE_BUILD_TYPE=$BUILD_TYPE -DCMAKE_C_FLAGS="$EXTRA_CMAKE_C_FLAGS \
 -g -sINLINING_LIMIT -O0 --pre-js $(pwd)/pre.js $POST_JS -sEXPORTED_FUNCTIONS=['_main','_git_strarray_print','_git_index_add_bypath','_malloc','_git_repository_open_ext','_git_repository_init','_git_libgit2_init','_git_repository_index','_git_index_add_all'] -s \"EXTRA_EXPORTED_RUNTIME_METHODS=['FS','callMain','ccall','cwrap','lengthBytesUTF8','stringToUTF8','writeArrayToMemory','getValue','setValue']\" -lnodefs.js -lidbfs.js -s INVOKE_RUN=0 -s ALLOW_MEMORY_GROWTH=1 -s TOTAL_MEMORY=512MB -s STACK_SIZE=131072" -DREGEX_BACKEND=regcomp -DSONAME=OFF -DUSE_HTTPS=OFF -DBUILD_SHARED_LIBS=OFF -DTHREADSAFE=OFF -DUSE_SSH=OFF -DBUILD_CLAR=OFF -DBUILD_EXAMPLES=ON ../libgit2

Please note: more EXPORTED_FUNCTIONS and EXTRA_EXPORTED_RUNTIME_METHODS.
Should I leave it like this or put them in a kind of variable?

Most of these exports are only needed for my example.

[petersalomonsen]

For this repo, I'd like to keep the single lg2 point of entry, and try to make sure that the CLI commands exposed are as similar to real GIT as possible ( though with limitations ). You can create your own fork with such exports if you want, but I would prefer not to include it in this repository.