Updated Assignments overview (markdown)

Assignments-overview.md

@@ -12,9 +12,9 @@ Job is a set/list of tasks (it is generally a set, but order of tasks have some
 
 Tasks are executed sequentially -- by the linear ordering of the task graph. Parallel tasks (tasks, which are not directly dependent and thus their linear ordering may be arbitrary) are ordered by their priority (first) and by their order in the configuration file (second). Priority is important for specifying evaluation flow. See sample picture for better understanding.
 
-_**TODO**_ insert picture
+![Picture of task serialization](https://github.com/ReCodEx/GlobalWiki/raw/master/images/Assignment_overview.png)
 
-Each task has a unique ID (alphanum string like _compile_, _test01_, or _judge01_). These IDs are used to identify tasks (for dependency references, in the log, ...).
+Each task has a unique ID (alphanum string like _CompileA_, _RunAA_, or _JudgeAB_ in the picture). These IDs are used to identify tasks (for dependency references, in the log, ...). Numbers in bottom right corner are priorities of each task. Higher number is greater priority. It means, that if task _RunAA_ is done, next must be _JudgeAA_ and not _RunAB_ (that will be also valid linear ordering, but _RunAB_ has lower priority).
 
 ### Task
 Task is an atomic piece of work executed by isoeval. There are two basic types of tasks (so far):