Changes to `tmc_blockentitymenu`

• Right-click context entity menu is re-enabled, regardless if `tmc_blockentitymenu` is enabled, only if the context key button (by default, 'C') is pressed. This supersedes a workaround where the user would need to lock the mouse cursor in order to right click the entity and do other actions
  
• Properly detour functions (need to check if they exist) to prevent infinite recursion

New concommand: "tmc_blockentitymenu [0/1]". Set it to 1 to disable context options when right-clicking on an entity

Add notification text and sound customization.

To replace text, navigate to "data/tmc/notification.json" in your GMod local filesystem. notification.json has the following contents:

If you do not see notification.json, or the path "tmc/notification.json" in the GMod data folder, you can create your own file and copy and paste the above contents.
Replace the "locked" and "unlocked" text with your own!

To replace sound, you must have an mp3 file named "notification" located in the "sound/tmc" directory in some addon folder in addons or in the GMod local filesystem. For example, the following are valid

Some formatting changes