Fix random search

[MaximSmolskiy]

Current random search implementation doesn't run.
In Octave:

>> random_search

error: parse error near line 19 of file D:\MATLAB-Octave\algorithms\Searching\random_search.m

  syntax error

>>>     best,=min(feval(ObjFun,candidate));

In MATLAB:

>> random_search
Error: File: random_search.m Line: 19 Column: 10
Incorrect use of '=' operator. To assign a value to a variable, use '='. To compare values
for equality, use '=='.

It has syntax error - redundant comma , in line 19:

best,=min(feval(ObjFun,candidate));