Update local MESSy-CLaMS repository

Get changes from remote repository

Fetch and merge changes on the remote server to your working directory:
```
git pull
```

See changes before pulling from remote git repository

Fetch changes from the remote repository:

git fetch

Show commit logs of changes / show diffs of changes:

git log --name-status devel..origin/devel
git diff --name-status devel origin/devel
git diff devel origin/devel

Apply the changes by merge or just pull the changes:

git merge 
or
git pull

Merging with local modification

If you pull from the remote repository and there are local uncommitted modifications in files that have also been changed in the remote repository, you will fail and get a message like this: "Please, commit your changes or stash them before you can merge."

Then you have three options:
1. Commit changes
```
git add ...
git commit ...
git pull
```
2. Stash changes
  
  Stashing acts as a stack, where you can push changes, and you pop them in reverse order. Stash, do the merge and then pull the stash:
```
git stash
git pull
git stash pop
```
3. Discard changes
  
  Discard all local changes to all files and get current version from remote repository:
```
git reset --hard origin/devel
git pull
```
  Discard local changes for a specific file:
```
git checkout -- filename
```