Merge pull request #378 from jeff1evesque/js_ajax_data

#376: Prevent unnecessary AJAX call in 'ajax_data.js'
#374: data_validator.py, use 'get()' to access JSON dict value
#374: data_validator.py, wrap 'file upload' validation with 'None' test
#374: data_validator.py, revert some code from '.get()' to bracket notation
Merge pull request #381 from jeff1evesque/python_data_validator

#374: Adjust 'data_validator.py', 'XML file' case
#374: data_validator.py, remove 'is not None'
Merge pull request #383 from jeff1evesque/python_data_validator

#374: data_validator.py, remove 'is not None'
#374: data_validator.py, provide 'else' statement
Merge pull request #384 from jeff1evesque/python_data_validator

#374: data_validator.py, provide 'else' statement
#387: data_validator.py, change 'Notice' -> 'Error'
Merge pull request #388 from jeff1evesque/python_data_validator

#387: data_validator.py, change 'Notice' -> 'Error'
#385: svm_training.py, implement wrapping 'IF' statement
#385: unnest 'elif' statement
Merge pull request #389 from jeff1evesque/python_svm_training

#385: Check file upload(s) in 'svm_training.py'
#386: svm_analysis.py, add comment
#386: svm_analysis.py, first nested 'IF' statement
#386: svm_analysis.py, remove unnececessary 'print' statement
Merge pull request #390 from jeff1evesque/python_svm_analysis

#368: Validate SVM properties in 'svm_analysis.py'
#385: svm_training.py, add 'None' parameter in '.get()'
Merge pull request #391 from jeff1evesque/python_svm_training

#385: svm_training.py, add 'None' parameter in '.get()'