docs: update descriptions to use 'Returns' and match JS formatting

Author: Planeshifter

lib/node_modules/@stdlib/stats/base/dists/t/variance/README.md

@@ -157,7 +157,7 @@ for ( i = 0; i < 10; i++ ) {
 
 #### stdlib_base_dists_t_variance( v )
 
-Evaluates the variance for a Student's t-distribution.
+Returns the variance for a Student's t-distribution.
 
 ```c
 double out = stdlib_base_dists_t_variance( 5.0 );
@@ -208,7 +208,7 @@ int main( void ) {
     for ( i = 0; i < 25; i++ ) {
         v = random_uniform( 2.1, 100.0 );
         y = stdlib_base_dists_t_variance( v );
-        printf( "v: %lf, variance: %lf\n", v, y );
+        printf( "v: %.4f, Var(X;v): %.4f\n", v, y );
     }
 }
 ```

lib/node_modules/@stdlib/stats/base/dists/t/variance/examples/c/example.c

@@ -33,6 +33,6 @@ int main( void ) {
 	for ( i = 0; i < 25; i++ ) {
 		v = random_uniform( 2.1, 100.0 );
 		y = stdlib_base_dists_t_variance( v );
-		printf( "v: %lf, variance: %lf\n", v, y );
+		printf( "v: %.4f, Var(X;v): %.4f\n", v, y );
 	}
 }

lib/node_modules/@stdlib/stats/base/dists/t/variance/include/stdlib/stats/base/dists/t/variance.h

@@ -27,10 +27,10 @@ extern "C" {
 #endif
 
 /**
-* Evaluates the variance for a Student's t-distribution with degrees of freedom `v`.
+* Returns the variance for a Student's t-distribution with degrees of freedom `v`.
 *
 * @param v    degrees of freedom
-* @return     evaluated variance
+* @return     variance
 *
 * @example
 * double y = stdlib_base_dists_t_variance( 5.0 );

lib/node_modules/@stdlib/stats/base/dists/t/variance/lib/native.js

@@ -26,11 +26,11 @@ var addon = require( './../src/addon.node' );
 // MAIN //
 
 /**
-* Evaluates the variance for a Student's t-distribution with degrees of freedom `v`.
+* Returns the variance for a Student's t-distribution with degrees of freedom `v`.
 *
 * @private
 * @param {number} v - degrees of freedom
-* @returns {number} evaluated variance
+* @returns {number} variance
 *
 * @example
 * var y = variance( 5.0 );

lib/node_modules/@stdlib/stats/base/dists/t/variance/src/main.c

@@ -19,10 +19,10 @@
 #include "stdlib/math/base/assert/is_nan.h"
 
 /**
-* Evaluates the variance for a Student's t-distribution with degrees of freedom `v`.
+* Returns the variance for a Student's t-distribution with degrees of freedom `v`.
 *
 * @param v    degrees of freedom
-* @return     evaluated variance
+* @return     variance
 *
 * @example
 * double y = stdlib_base_dists_t_variance( 5.0 );