Create the testcases for Descriptive statics ,standard deviation and probability distribution calculation

Add EssayTypeQuestionsActivity in AndroidManifest.xml file

See merge request !71

Update verification screen

See merge request !70

# Conflicts:
#   app/build.gradle

Currently modified ProbabilityDistributionQuestionComparation java class

See merge request !69

Updated the issues in manifest and build gradle

See merge request !68

# Conflicts:
#	app/build.gradle
#	app/src/main/AndroidManifest.xml

Create probability distribution calculation for dataset, test standard deviation function and descriptive statistics function.

See merge request !66

# Conflicts:
#   app/src/main/java/com/elearning/probabilityandstatisticsanalyserandeducator/dataExtraction/ProbabilityDistributionQuestionComparation.java
#   app/src/main/java/com/elearning/probabilityandstatisticsanalyserandeducator/inputMethod/ProbabilityDistributionsIM.java

Extract dataset from essay type probability distribution questions

See merge request !67