Fix CppCheck style errors

#if 0 the content of toxav/msi.c : int stringify_message(MSIMessage
*msg, char *dest)
This function has no effect and does not seem to be used for actively
waiting.

Fix various other style errors, reduce scope when possible, avoid
redundant writes, clarify operator priorities, etc.
Started with VAD
Got a little dated
Reduced number of realloc calls bs_list does
Fix FreeBSD instructions, sodium 0.5.0

Sodium 0.5.0 optimizes itself on being loaded
Update README.md
Added strkey
Fixed sodium include
Merge branch 'tux3-cppcheck-style'
Merge branch 'patch-1' of https://github.com/stqism/ToxCore
Fixed a case when public key contained null bytes
Added tolerance to VAD and lowered Jitter buffer default value
Merge branch 'strkey' of https://github.com/nurupo/InsertProjectNameHere
Merged upstream
Merge branch 'list-fix' of https://github.com/nurupo/InsertProjectNameHere
Fixed possible issues with list introduced in the last commit.
Merge branch 'master' of https://github.com/mannol1/toxcore
Removed hamful code
Merge branch 'master' of https://github.com/mannol1/toxcore
basic packet splitting for video frames