Max length in abstracts should be characters or words

[jbenito]

Allow to set it up to words.

[Alexis Castilla Hernandez <alexis.castilla.hernandez@…>]

In [39b7d05690b26d2fbb4307bc393f482819e1a0a2/indico]:

[IMP] Abstract submittion form

• Allow to choose limit for fields of the abstract submittion form in chars or words.
• Added attribute "limitation" to class AbstractField?.
• Included word counter tool in JS (Data.js) and Python (util/text.py).
• Added parameter manager in the interface of adding a new field to the submittion abstract form.
• Added parameter manager in fields limited by words or chars.
• Added parameter manager to mandatory fields in abstract submittion form (conference display).
• Done title mandatory in abstract submittion form (management).
• Changes applied to everywhere you can display the submition form.
• Fixed: show track title in the form only if there are tracks.
• Added difference between input and text area in abstract submittion form (management).
• Added new Management/CFA.js file.
• Added new util/text.py file.
• Changed notification templates vars format |var| -> {var}
• Deleted unnecessary code found in /webinterface/pages/conferences.py of notification templates.
• Closes #694