Correct math for detecting allowed file size during upload

1. create "kUtil::parseIniSize($size)" method, that will: - 0.5h
   • if value is integer, then return it as-as
   • if value contains K/M/G shorthand (case insensitive) then return numeric part multiplied by byte equivalent for a particular shorthand
2. in "startup.php" use this logic for "MAX_UPLOAD_SIZE" constant value detection: - 0.5h
   1. start with "kUtil::parseIniSize" processed value of "upload_max_filesize" setting
   2. get value of "post_max_size" setting and when it's value isn't "0" (means we have restrictions), then:
      1. use "kUtil::parseIniSize" function on it
      2. choose smallest value between this one and previous one
   3. get value of "memory_limit" setting and when it's value isn't "-1" (means we have restrictions), then:
      1. use "kUtil::parseIniSize" function on it
      2. choose smallest value between this one and previous one
   4. set "MAX_UPLOAD_SIZE" to result above calculations

Quote: 1h*1.4=1.5h