Metric of PsiContext for Java and Python

[phodal]

Is your feature request related to a problem? Please describe.
No

Describe the solution you'd like
Support for metric element metric, add to PsiContextVariable.kt

• changeCount
• lineCount
• complexityCount

Describe alternatives you've considered
Similar project: https://github.com/nikolaikopernik/code-complexity-plugin

Additional context
implementation simple changeCount, lineCount, complexityCount function in PsiContextVariableProvider

1. changeCount analysis current psiElement.containingFile git change
2. lineCount count current containingFile length
3. complexityCount create a new interface like (ComplexityProvider) to analysis complexity, create visitor to visit element, like:
   • every language (java , kotlin) should implementation ComplexityProvider
   • Based on langauge syntax to generate Point

ElementVisitor example

package com.github.nikolaikopernik.codecomplexity.core

import com.intellij.psi.PsiElement
import com.intellij.psi.PsiRecursiveElementVisitor

abstract class ElementVisitor : PsiRecursiveElementVisitor(true) {
    override fun visitElement(element: PsiElement) {
        processElement(element)
        if (shouldVisitElement(element)) {
            super.visitElement(element)
        }
        postProcess(element)
    }

    /**
     * Increases complexity and nesting
     */
    protected abstract fun processElement(element: PsiElement)

    /**
     * Decreases nesting
     */
    protected abstract fun postProcess(element: PsiElement)

    /**
     * @return true if PsiElement is Binary Expression with operations || or &&
     */
    protected abstract fun shouldVisitElement(element: PsiElement): Boolean
}