Squashed 'git@github.com:christkv/learn-mongodb-docs.git/' content from commit 5101045

git-subtree-dir: git@github.com:christkv/learn-mongodb-docs.git
git-subtree-split: 5101045c3e7e3cf50e1683cbffc026a7bb0e9d92
Merge commit 'd9a853d439e17245bc1d597543a6483660480112' as 'git@github.com:christkv/learn-mongodb-docs.git'
Fixed makefile