Added empty python files for future functions

Added empty python files that will be filled up with the functions of
the PoE application later.
Added class items and function importItems to stats.py

Added an items class together with the first function importItems to
stats.py. The importItems function reads a file called items.txt, which
should contain the character information from the PoE website in JSON
format and returns a dictionary that contains the information.
Renamed itemlist.txt to items.txt

Renamed the itemlist file
Added unittest file for stats module

sadasda
Added class variables for added damage, attack speed and crit

Added class variables to the stats.py module to store mods on gear
related to increasing damage
Added new functions to stats.py

Added a function to retrieve the implicit and explicit mods on items,
added a function to create a dictionary that contains the explicit and
implicit mods for each equipped item
Added a full inventory class variable
Added a dictionary that contains the items that are actually equipped
Add function extractdamagestats

Added the function extractdamagestats which currently retrieves all the
explicit and implicit mods from items and print them. In the future,
this function will update the damage increase class variable according
to the mods on gear
Added dictionary to store stats on items

Added a class variable itemstats to store the mods on the equipped
items, such as increased attack speed, elemental resistances and added
damage. More stats will be added in a later stage.
Added code to extractitemstats to extract elemental resistances

Added code to the extractitemstats function of the stats.py module to
extract the added elemental resistances on gear
Added extraction of additional mods to extractitemstats

Added extraction of additional mods to the extractitemstats function of
the stats.py module.

TODO:
- Extract physical damage, chaos damage, crit chance and multi
- Extract implicit mods
- Add fire/cold, cold/lightning and lightning/fire res extraction to
implicit mods for Two-Stone Rings
Added Skillgems class to skills.py module

Added the Skillgems class to the skills.py module, with an __init__
method that contains empty dictionaries for the active and support gems.
Update stats.py and add a document with functional requirements

Added changes to stats.py (this file will be deleted in the future) and
created a file with a list of functions per module of the project
Added calculation functions to calculate.py

Added empty calculation functions to the calculate.py module. These
functions will be filled up with the actual code later.
Create working version of function calculate_mana_cost

Created a working version of the calculate_mana_cost function that
calculates the mana cost of a skill based on the linked support gems.
The resulted value is rounded up so it actually is an integer.
Updated calculate.py and functionslist

Added code to the following functions in calculate.py:
- calculate_mana_cost
- calculate_damage_per_second
- calculate_crit_chance

Also added calls to the functions to test the in-game values. This will
be added to unittests later. The unittests will be updated on a regular
basis with the actual values to be able to compare them to the actual
values.
Filled in functions in calculate.py

This is a very crappy, way too large commit that should have been broken
up into several smaller commits but in this case I cba.
Add file with skill tags

Added the file skill_tags.csv which contains all the active skills,
together with the tags that are attached to each active skill
Add strength gem tags to skill_tags.csv

Added the tags attached to active skills with main attribute strength to
the skill_tags.csv file. Tags of skill gems with main attributes
dexterity and intelligence will follow later.
Add dexterity gems to skill_tags.csv

Added the keywords for gems with main attribute dexterity to the
skill_tags.csv file
Add active int skills to skill_tags.csv

Added the active skill gems with main stat intelligence along with the
related keywords to the skill_tags.csv file