flexible directories are now optional use

[ayham-1]

Add option to use hard-coded directories when cloning contests/problems.

By default this feature is turned on.

[MuhammadSawalhy]

Great! Waiting for this feature

[xeluxee]

I suggest the following changes:

• remove use_flexible_directories option
• contests_directory should accept one of the following values:
  • false to use flexible directories
  • string to specify contest directory
• add an option problems_directory for received problems, that is configured similarly to contests_directory

[xeluxee]

As @MuhammadSawalhy pointed out, users could prefer functions to configure contest directory.

So both contests_directory and problems_directory should accept one of the following values:

• false to use flexible directories
• string to specify contest directory (with new receive-modifiers)
• function with one argument, a table with fields problem, group, url

I'd like to introduce a new set of modifiers, the receive-modifiers, that should be kept separated from file format modifiers and should be used to evaluate contests_directory, problems_directory and comments in template files (from #39):

modifier	meaning
$(PROBLEM)	Problem name, name field
$(GROUP)	judge and contest name, group field
$(JUDGE)	first part of group, before hyphen
$(CONTEST)	second part of group, after hyphen
$(URL)	problem url, url field
$(MEMLIM)	available memory, memoryLimit field
$(TIMELIM)	time limit, timeLimit field
$(HOME)	home directory
$(DATE)	current time, following date_format

Note that $(GROUP), $(JUDGE) and $(CONTEST) are different modifiers, but the latter two modifiers are generated from the former. Also $(MEMLIM), $(TIMELIM) and $(DATE) are meant to be used in template files only.

Is these enough to reach an agreement on #28? @ayham-1 @MuhammadSawalhy

[MuhammadSawalhy]

Seams like I need to learn Lua and get a deep dive into this PR!

[xeluxee]

Closing with #40 See how to customize folder structure for received problems and contests.