Fill README of some plugins. Closes GH-747. Closes GH-749.

plugins/Conditional/README.md

@@ -1 +1,5 @@
-Insert a description of your plugin here, with any notes, etc. about using it.
+Provides a bunch of commands that enables you to run other commands based
+on a condition.
+Also provides logic operators for writing conditions.
+
+Useful for bot scripting / nested commands.

plugins/Protector/README.md

@@ -1 +1,2 @@
-Insert a description of your plugin here, with any notes, etc. about using it.
+Prevent users from doing things they are not supposed to do on a channel,
+even if they have +o or +h.

plugins/QuoteGrabs/README.md

@@ -1 +1,2 @@
-Insert a description of your plugin here, with any notes, etc. about using it.
+Stores and displays quotes from channels. Quotes are stored randomly
+and/or on user request.

plugins/String/README.md

@@ -1 +1 @@
-Insert a description of your plugin here, with any notes, etc. about using it.
+Useful commands for manipulating characters strings.

plugins/Unix/README.md

@@ -1 +1 @@
-Insert a description of your plugin here, with any notes, etc. about using it.
+Utilities for Unix-like systems.

plugins/Utilities/README.md

@@ -1 +1 @@
-Insert a description of your plugin here, with any notes, etc. about using it.
+Provides useful commands for bot scripting / commands nesting.