Merge pull request #1 from voxik/master

More descriptive README
Merge pull request #2 from voxik/master

Visual fixes to README
Use exec to prevent creating new process.

Creating new process might have some side effects, such as changing
PID. Some script might depend on it.
Merge pull request #3 from voxik/exec

Use exec to prevent creating new process.
Remove one excess space.