Make it build with LaTeX

Rewritten-docs.md

@@ -334,11 +334,11 @@ can look like this:
 
 ```
 Summer term 2016
-├── Language C# and .NET platform
-│   ├── Labs Monday 10:30
-│   └── Labs Thursday 9:00
-├── Programming I
-│   ├── Labs Monday 14:00
+|-- Language C# and .NET platform
+|   |-- Labs Monday 10:30
+|   `-- Labs Thursday 9:00
+|-- Programming I
+|   |-- Labs Monday 14:00
  ...
 
 ```
@@ -371,7 +371,7 @@ languages) including specific time and memory limits for the sandboxed tasks.
 The most important part of the system is the evaluation of the solutions
 submitted by the users for their assigned exercises. Concepts of consecutive
 steps from source code of solution to results is described on architecture with
-two layer -- presentation (frontend) and executive (backend).
+two layer -- presentation (_frontend_) and executive (_backend_).
 
 First thing users have to do is to submit their solutions to _frontend_ which
 provides interface to upload files and then submit them. It checks the
@@ -408,7 +408,7 @@ overview which part succeeded and which failed (optionally with reason like
 
 @todo: what problems were solved on abstract and high levels, how they can be solved and what was the final solution
 
-- which problems are they? ... these ones ↓
+- which problems are they? ... these ones below:
 - what type of users there should be, why they are needed
 - explain why there is exercise and assignment division, what means what and how they are used
 - explain instances why they are usefull what they solve and also discuss licences concept