Diff and patch modification (close #34)

# Temporary files

sharelatex/

sharelatex_ori/

# Compiled Object files

*.slo

*.lo

This repo contains an improved, free ldap authentication and authorisation 

for sharelatex/[overleaf](https://github.com/overleaf/overleaf) community 

edition. Currently this repo uses sharelatex:latest.

edition. Currently this repo uses `sharelatex/sharelatex:4.1.1`.

The inital idea for this implementation was taken from 

[worksasintended](https://github.com/worksasintended).

1. Set the env variable `LOG_LEVEL` to `debug` (default is info - you can do this in the docker-compose file)

2. Check the logs in ShareLaTeX, particularly at `/var/log/sharelatex/web.log`. You can do this by using the command: `docker exec ldap-overleaf-sl cat /var/log/sharelatex/web.log`.

## Development

1. Cloning this repo

2. Extract files from image using `bash scripts/extract_files SHARELATEX_VERSION`

3. Generate modified files using `bash scripts/apply_patches.js`

4. Development

5. Create diff files using `bash script/make_diffs.sh` and commit

## Upgrading

*Be aware:* if you upgrade from a previous installation check your docker image version